Misplaced Pages

This is an old revision of this page, as edited by Sweety439 (talk | contribs) at 22:17, 6 December 2020 (→General). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Since the Renaissance, every century has seen the solution of more mathematical problems than the century before, yet many mathematical problems, both major and minor, still remain unsolved. These unsolved problems occur in multiple domains, including physics, computer science, algebra, analysis, combinatorics, algebraic, differential, discrete and Euclidean geometries, graph, group, model, number, set and Ramsey theories, dynamical systems, partial differential equations, and more. Some problems may belong to more than one discipline of mathematics and be studied using techniques from different areas. Prizes are often awarded for the solution to a long-standing problem, and lists of unsolved problems (such as the list of Millennium Prize Problems) receive considerable attention.

This article is a composite of unsolved problems derived from many sources, including but not limited to lists considered authoritative. It does not claim to be comprehensive, it may not always be quite up to date, and it includes problems which are considered by the mathematical community to be widely varying in both difficulty and centrality to the science as a whole.

Lists of unsolved problems in mathematics

Various mathematicians and organizations have published and promoted lists of unsolved mathematical problems. In some cases, the lists have been associated with prizes for the discoverers of solutions.

Millennium Prize Problems

Of the original seven Millennium Prize Problems set by the Clay Mathematics Institute in 2000, six have yet to be solved as of July, 2020:

• P versus NP
• Hodge conjecture
• Riemann hypothesis
• Yang–Mills existence and mass gap
• Navier–Stokes existence and smoothness
• Birch and Swinnerton-Dyer conjecture

The seventh problem, the Poincaré conjecture, has been solved; however, a generalization called the smooth four-dimensional Poincaré conjecture—that is, whether a four-dimensional topological sphere can have two or more inequivalent smooth structures—is still unsolved.

Unsolved problems

Algebra

• Homological conjectures in commutative algebra
• Finite lattice representation problem
• Hilbert's sixteenth problem
• Hilbert's fifteenth problem
• Hadamard conjecture
• Jacobson's conjecture
• Crouzeix's conjecture
• Existence of perfect cuboids and associated cuboid conjectures
• Zauner's conjecture: existence of SIC-POVMs in all dimensions
• Wild problem: Classification of pairs of n×n matrices under simultaneous conjugation and problems containing it such as a lot of classification problems
• Köthe conjecture
• Birch–Tate conjecture
• Serre's conjecture II
• Bombieri–Lang conjecture
• Farrell–Jones conjecture
• Bost conjecture
• Rota's basis conjecture
• Uniformity conjecture
• Kaplansky's conjectures
• Kummer–Vandiver conjecture
• Serre's multiplicity conjectures
• Pierce–Birkhoff conjecture
• Eilenberg–Ganea conjecture
• Green's conjecture
• Grothendieck–Katz p-curvature conjecture
• Sendov's conjecture
• Zariski–Lipman conjecture
• The Dneister Notebook (Dnestrovskaya Tetrad) collects several hundred unresolved problems in algebra, particularly ring theory and modulus theory.
• The Erlagol Notebook (Erlagolskaya Tetrad) collects unresolved problems in algebra and model theory.

Analysis

• The four exponentials conjecture on the transcendence of at least one of four exponentials of combinations of irrationals
• Lehmer's conjecture on the Mahler measure of non-cyclotomic polynomials
• The Pompeiu problem on the topology of domains for which some nonzero function has integrals that vanish over every congruent copy
• Schanuel's conjecture on the transcendence degree of exponentials of linearly independent irrationals
• Are ${\displaystyle \gamma }$ (the Euler–Mascheroni constant), π + e, π − e, πe, π/e, π, π, π, e, ln π, 2, e, Catalan's constant, or Khinchin's constant rational, algebraic irrational, or transcendental? What is the irrationality measure of each of these numbers?
• Vitushkin's conjecture
• Invariant subspace problem
• Kung–Traub conjecture
• Regularity of solutions of Vlasov–Maxwell equations
• Regularity of solutions of Euler equations
• Convergence of Flint Hills series

Combinatorics

• Frankl's union-closed sets conjecture: for any family of sets closed under sums there exists an element (of the underlying space) belonging to half or more of the sets
• The lonely runner conjecture: if ${\displaystyle k+1}$ runners with pairwise distinct speeds run round a track of unit length, will every runner be "lonely" (that is, be at least a distance ${\displaystyle 1/(k+1)}$ from each other runner) at some time?
• Finding a function to model n-step self-avoiding walks.
• The 1/3–2/3 conjecture: does every finite partially ordered set that is not totally ordered contain two elements x and y such that the probability that x appears before y in a random linear extension is between 1/3 and 2/3?
• Give a combinatorial interpretation of the Kronecker coefficients.
• Open questions concerning Latin squares
• The values of the Dedekind numbers ${\displaystyle M(n)}$ for ${\displaystyle n\geq 9}$.
• The values of the Ramsey numbers, particularly ${\displaystyle R(5,5)}$
• The values of the Van der Waerden numbers

Dynamical systems

• Collatz conjecture (3n + 1 conjecture)
• Lyapunov's second method for stability – For what classes of ODEs, describing dynamical systems, does the Lyapunov’s second method formulated in the classical and canonically generalized forms define the necessary and sufficient conditions for the (asymptotical) stability of motion?
• Furstenberg conjecture – Is every invariant and ergodic measure for the ${\displaystyle \times 2,\times 3}$ action on the circle either Lebesgue or atomic?
• Margulis conjecture – Measure classification for diagonalizable actions in higher-rank groups
• MLC conjecture – Is the Mandelbrot set locally connected?
• Weinstein conjecture – Does a regular compact contact type level set of a Hamiltonian on a symplectic manifold carry at least one periodic orbit of the Hamiltonian flow?
• Arnold–Givental conjecture and Arnold conjecture – relating symplectic geometry to Morse theory
• Eremenko's conjecture that every component of the escaping set of an entire transcendental function is unbounded
• Is every reversible cellular automaton in three or more dimensions locally reversible?
• Birkhoff conjecture: if a billiard table is strictly convex and integrable, is its boundary necessarily an ellipse?
• Many problems concerning an outer billiard, for example showing that outer billiards relative to almost every convex polygon have unbounded orbits.
• Quantum unique ergodicity conjecture
• Berry–Tabor conjecture
• Painlevé conjecture

Games and puzzles

Combinatorial games

• Sudoku:
  • What is the maximum number of givens for a minimal puzzle?
  • How many puzzles have exactly one solution?
  • How many puzzles with exactly one solution are minimal?
• Tic-tac-toe variants:
  • Given a width of tic-tac-toe board, what is the smallest dimension such that X is guaranteed a winning strategy?
• What is the Turing completeness status of all unique elementary cellular automata?

Games with imperfect information

• Rendezvous problem

Geometry

Algebraic geometry

• Abundance conjecture
• Bass conjecture
• Deligne conjecture
• Dixmier conjecture
• Fröberg conjecture
• Fujita conjecture
• Hartshorne conjectures
• The Jacobian conjecture
• Manin conjecture
• Maulik–Nekrasov–Okounkov–Pandharipande conjecture on an equivalence between Gromov–Witten theory and Donaldson–Thomas theory
• Nakai conjecture
• Resolution of singularities in characteristic ${\displaystyle p}$
• Standard conjectures on algebraic cycles
• Section conjecture
• Tate conjecture
• Termination of flips
• Virasoro conjecture
• Weight-monodromy conjecture
• Zariski multiplicity conjecture

Differential geometry

• The filling area conjecture, that a hemisphere has the minimum area among shortcut-free surfaces in Euclidean space whose boundary forms a closed curve of given length
• The Hopf conjectures relating the curvature and Euler characteristic of higher-dimensional Riemannian manifolds
• The spherical Bernstein's problem, a possible generalization of the original Bernstein's problem
• Cartan–Hadamard conjecture: Can the classical isoperimetric inequality for subsets of Euclidean space be extended to spaces of nonpositive curvature, known as Cartan–Hadamard manifolds?
• Carathéodory conjecture
• Chern's conjecture (affine geometry)
• Chern's conjecture for hypersurfaces in spheres
• Yau's conjecture
• Yau's conjecture on the first eigenvalue
• Closed curve problem: Find (explicit) necessary and sufficient conditions that determine when, given two periodic functions with the same period, the integral curve is closed.

Discrete geometry

• Solving the happy ending problem for arbitrary ${\displaystyle n}$
• Finding matching upper and lower bounds for k-sets and halving lines
• The Hadwiger conjecture on covering n-dimensional convex bodies with at most 2 smaller copies
• Find lower and upper bounds for Borsuk's problem on the number of smaller-diameter subsets needed to cover a bounded n-dimensional set.
• The Kobon triangle problem on triangles in line arrangements
• The McMullen problem on projectively transforming sets of points into convex position
• Tripod packing
• Ulam's packing conjecture about the identity of the worst-packing convex solid
• Sphere packing problems, including the density of the densest packing in dimensions other than 1, 2, 3, 8 and 24, and its asymptotic behavior for high dimensions.
• What is the asymptotic growth rate of wasted space for packing unit squares into a half-integer square?
• Kissing number problem for dimensions other than 1, 2, 3, 4, 8 and 24
• How many unit distances can be determined by a set of n points in the Euclidean plane?
• Opaque forest problem
• Improving lower and upper bounds for the Heilbronn triangle problem.
• Kalai's 3^d conjecture on the least possible number of faces of centrally symmetric polytopes.

Euclidean geometry

• Bellman's lost in a forest problem – find the shortest route that is guaranteed to reach the boundary of a given shape, starting at an unknown point of the shape with unknown orientation
• Borromean rings — are there three unknotted space curves, not all three circles, which cannot be arranged to form this link?
• Danzer's problem and Conway's dead fly problem – do Danzer sets of bounded density or bounded separation exist?
• Dissection into orthoschemes – is it possible for simplices of every dimension?
• The einstein problem – does there exist a two-dimensional shape that forms the prototile for an aperiodic tiling, but not for any periodic tiling?
• The Erdős–Oler conjecture that when ${\displaystyle n}$ is a triangular number, packing ${\displaystyle n-1}$ circles in an equilateral triangle requires a triangle of the same size as packing ${\displaystyle n}$ circles
• Falconer's conjecture that sets of Hausdorff dimension greater than ${\displaystyle d/2}$ in ${\displaystyle \mathbb {R} ^{d}}$ must have a distance set of nonzero Lebesgue measure
• Inscribed square problem, also known as Toeplitz' conjecture – does every Jordan curve have an inscribed square?
• The Kakeya conjecture – do ${\displaystyle n}$-dimensional sets that contain a unit line segment in every direction necessarily have Hausdorff dimension and Minkowski dimension equal to ${\displaystyle n}$?
• The Kelvin problem on minimum-surface-area partitions of space into equal-volume cells, and the optimality of the Weaire–Phelan structure as a solution to the Kelvin problem
• Lebesgue's universal covering problem on the minimum-area convex shape in the plane that can cover any shape of diameter one
• Moser's worm problem – what is the smallest area of a shape that can cover every unit-length curve in the plane?
• The moving sofa problem – what is the largest area of a shape that can be maneuvered through a unit-width L-shaped corridor?
• Shephard's problem (a.k.a. Dürer's conjecture) – does every convex polyhedron have a net, or simple edge-unfolding?
• The Thomson problem – what is the minimum energy configuration of ${\displaystyle n}$ mutually-repelling particles on a unit sphere?
• Uniform 5-polytopes – find and classify the complete set of these shapes
• Covering problem of Rado – if the union of finitely many axis-parallel squares has unit area, how small can the largest area covered by a disjoint subset of squares be?
• Atiyah conjecture on configurations
• Mahler's conjecture on the product of the volumes of a centrally symmetric convex body and its polar.

Graph theory

Paths and cycles in graphs

• Barnette's conjecture that every cubic bipartite three-connected planar graph has a Hamiltonian cycle
• Chvátal's toughness conjecture, that there is a number t such that every t-tough graph is Hamiltonian
• The cycle double cover conjecture that every bridgeless graph has a family of cycles that includes each edge twice
• The Erdős–Gyárfás conjecture on cycles with power-of-two lengths in cubic graphs
• The linear arboricity conjecture on decomposing graphs into disjoint unions of paths according to their maximum degree
• The Lovász conjecture on Hamiltonian paths in symmetric graphs
• The Oberwolfach problem on which 2-regular graphs have the property that a complete graph on the same number of vertices can be decomposed into edge-disjoint copies of the given graph.

Graph coloring and labeling

• Cereceda's conjecture on the diameter of the space of colorings of degenerate graphs
• The Erdős–Faber–Lovász conjecture on coloring unions of cliques
• The Gyárfás–Sumner conjecture on χ-boundedness of graphs with a forbidden induced tree
• The Hadwiger conjecture relating coloring to clique minors
• The Hadwiger–Nelson problem on the chromatic number of unit distance graphs
• Jaeger's Petersen-coloring conjecture that every bridgeless cubic graph has a cycle-continuous mapping to the Petersen graph
• The list coloring conjecture that, for every graph, the list chromatic index equals the chromatic index
• The total coloring conjecture of Behzad and Vizing that the total chromatic number is at most two plus the maximum degree

Graph drawing

• The Albertson conjecture that the crossing number can be lower-bounded by the crossing number of a complete graph with the same chromatic number
• The Blankenship–Oporowski conjecture on the book thickness of subdivisions
• Conway's thrackle conjecture
• Harborth's conjecture that every planar graph can be drawn with integer edge lengths
• Negami's conjecture on projective-plane embeddings of graphs with planar covers
• The strong Papadimitriou–Ratajczak conjecture that every polyhedral graph has a convex greedy embedding
• Turán's brick factory problem – Is there a drawing of any complete bipartite graph with fewer crossings than the number given by Zarankiewicz?
• Universal point sets of subquadratic size for planar graphs

Word-representation of graphs

• Characterise (non-)word-representable planar graphs
• Characterise word-representable near-triangulations containing the complete graph K₄ (such a characterisation is known for K₄-free planar graphs )
• Classify graphs with representation number 3, that is, graphs that can be represented using 3 copies of each letter, but cannot be represented using 2 copies of each letter
• Is the line graph of a non-word-representable graph always non-word-representable?
• Are there any graphs on n vertices whose representation requires more than floor(n/2) copies of each letter?
• Is it true that out of all bipartite graphs crown graphs require longest word-representants?
• Characterise word-representable graphs in terms of (induced) forbidden subgraphs.
• Which (hard) problems on graphs can be translated to words representing them and solved on words (efficiently)?

Miscellaneous graph theory

• Conway's 99-graph problem: does there exist a strongly regular graph with parameters (99,14,1,2)?
• The Erdős–Hajnal conjecture on large cliques or independent sets in graphs with a forbidden induced subgraph
• The GNRS conjecture on whether minor-closed graph families have ${\displaystyle \ell _{1}}$ embeddings with bounded distortion
• Graham's pebbling conjecture on the pebbling number of Cartesian products of graphs
• The implicit graph conjecture on the existence of implicit representations for slowly-growing hereditary families of graphs
• Jørgensen's conjecture that every 6-vertex-connected K₆-minor-free graph is an apex graph
• Meyniel's conjecture that cop number is ${\displaystyle O({\sqrt {n}})}$
• Does a Moore graph with girth 5 and degree 57 exist?
• What is the largest possible pathwidth of an n-vertex cubic graph?
• The reconstruction conjecture and new digraph reconstruction conjecture on whether a graph is uniquely determined by its vertex-deleted subgraphs.
• The second neighborhood problem: does every oriented graph contain a vertex for which there are at least as many other vertices at distance two as at distance one?
• Do there exist infinitely many strongly regular geodetic graphs, or any strongly regular geodetic graphs that are not Moore graphs?
• Sumner's conjecture: does every ${\displaystyle (2n-2)}$-vertex tournament contain as a subgraph every ${\displaystyle n}$-vertex oriented tree?
• Tutte's conjectures that every bridgeless graph has a nowhere-zero 5-flow and every Petersen-minor-free bridgeless graph has a nowhere-zero 4-flow
• Vizing's conjecture on the domination number of cartesian products of graphs

Group theory

• Is every finitely presented periodic group finite?
• The inverse Galois problem: is every finite group the Galois group of a Galois extension of the rationals?
• For which positive integers m, n is the free Burnside group B(m,n) finite? In particular, is B(2, 5) finite?
• Is every group surjunctive?
• Andrews–Curtis conjecture
• Herzog–Schönheim conjecture
• Does generalized moonshine exist?
• Are there an infinite number of Leinster groups?
• Guralnick–Thompson conjecture
• Problems in loop theory and quasigroup theory consider generalizations of groups
• The Kourovka Notebook is a collection of unsolved problems in group theory, first published in 1965 and updated many times since.

Model theory and formal languages

• Vaught's conjecture
• The Cherlin–Zilber conjecture: A simple group whose first-order theory is stable in ${\displaystyle \aleph _{0}}$ is a simple algebraic group over an algebraically closed field.
• The Main Gap conjecture, e.g. for uncountable first order theories, for AECs, and for ${\displaystyle \aleph _{1}}$-saturated models of a countable theory.
• Determine the structure of Keisler's order
• The stable field conjecture: every infinite field with a stable first-order theory is separably closed.
• Is the theory of the field of Laurent series over ${\displaystyle \mathbb {Z} _{p}}$ decidable? of the field of polynomials over ${\displaystyle \mathbb {C} }$?
• (BMTO) Is the Borel monadic theory of the real order decidable? (MTWO) Is the monadic theory of well-ordering consistently decidable?
• The Stable Forking Conjecture for simple theories
• For which number fields does Hilbert's tenth problem hold?
• Assume K is the class of models of a countable first order theory omitting countably many types. If K has a model of cardinality ${\displaystyle \aleph _{\omega _{1}}}$ does it have a model of cardinality continuum?
• Shelah's eventual categoricity conjecture: For every cardinal ${\displaystyle \lambda }$ there exists a cardinal ${\displaystyle \mu (\lambda )}$ such that If an AEC K with LS(K)<= ${\displaystyle \lambda }$ is categorical in a cardinal above ${\displaystyle \mu (\lambda )}$ then it is categorical in all cardinals above ${\displaystyle \mu (\lambda )}$.
• Shelah's categoricity conjecture for ${\displaystyle L_{\omega _{1},\omega }}$: If a sentence is categorical above the Hanf number then it is categorical in all cardinals above the Hanf number.
• Is there a logic L which satisfies both the Beth property and Δ-interpolation, is compact but does not satisfy the interpolation property?
• If the class of atomic models of a complete first order theory is categorical in the ${\displaystyle \aleph _{n}}$, is it categorical in every cardinal?
• Is every infinite, minimal field of characteristic zero algebraically closed? (Here, "minimal" means that every definable subset of the structure is finite or co-finite.)
• Kueker's conjecture
• Does there exist an o-minimal first order theory with a trans-exponential (rapid growth) function?
• Does a finitely presented homogeneous structure for a finite relational language have finitely many reducts?
• Do the Henson graphs have the finite model property?
• The universality problem for C-free graphs: For which finite sets C of graphs does the class of C-free countable graphs have a universal member under strong embeddings?
• The universality spectrum problem: Is there a first-order theory whose universality spectrum is minimum?
• Generalized star height problem

Number theory

General

• Grand Riemann hypothesis
  • Generalized Riemann hypothesis
    • Riemann hypothesis
• n conjecture
  • abc conjecture
  • Szpiro's conjecture
• Hilbert's ninth problem
• Hilbert's eleventh problem
• Hilbert's twelfth problem
• Carmichael's totient function conjecture
• Erdős–Straus conjecture
• Erdős–Ulam problem
• Pillai's conjecture
• Hall's conjecture
• Lindelöf hypothesis and its consequence, the density hypothesis for zeroes of the Riemann zeta function (see Bombieri–Vinogradov theorem)
• Montgomery's pair correlation conjecture
• Hilbert–Pólya conjecture
• Grimm's conjecture
• Leopoldt's conjecture
• Scholz conjecture
• Do any odd perfect numbers exist?
• Are there infinitely many perfect numbers?
• Do quasiperfect numbers exist?
• Do any odd weird numbers exist?
• Do any Lychrel numbers exist?
• Is 10 a solitary number?
• Catalan–Dickson conjecture on aliquot sequences
• Do any Taxicab(5, 2, n) exist for n > 1?
• Do any Taxicab(k, 2, n) exist for k > 4 and n > 1?
• Beal conjecture
• Fermat–Catalan conjecture: Are there any solutions other than these?

${\displaystyle 1^{m}+2^{3}=3^{2}\;}$

${\displaystyle 2^{5}+7^{2}=3^{4}\;}$

${\displaystyle 7^{3}+13^{2}=2^{9}\;}$

${\displaystyle 2^{7}+17^{3}=71^{2}\;}$

${\displaystyle 3^{5}+11^{4}=122^{2}\;}$

${\displaystyle 33^{8}+1549034^{2}=15613^{3}\;}$

${\displaystyle 1414^{3}+2213459^{2}=65^{7}\;}$

${\displaystyle 9262^{3}+15312283^{2}=113^{7}\;}$

${\displaystyle 17^{7}+76271^{3}=21063928^{2}\;}$

${\displaystyle 43^{8}+96222^{3}=30042907^{2}\;}$

• Brocard's problem: existence of integers, (n,m), such that n! + 1 = m other than n = 4, 5, 7
• Beilinson conjecture
• Littlewood conjecture
• Vojta's conjecture
• Goormaghtigh conjecture
• Congruent number problem (a corollary to Birch and Swinnerton-Dyer conjecture, per Tunnell's theorem)
• Lehmer's totient problem: if φ(n) divides n−1, must n be prime?
• Are there any number n such that there is exactly one integer m such that φ(m) = n?
• Are there infinitely many perfect numbers?
• Are there any odd perfect numbers?
• Are there any almost perfect numbers other than powers of 2?
• Are there any quasiperfect numbers?
• Are there infinitely many amicable numbers?
• Are there any pairs of amicable numbers which have opposite parity?
• Are there any pairs of relatively prime amicable numbers?
• Are there infinitely many betrothed numbers?
• Are there any pairs of betrothed numbers which have same parity?
• Are there infinitely many sociable number cycles?
• Are there any sociable number cycles with length 3?
• The Gauss circle problem – how far can the number of integer points in a circle centered at the origin be from the area of the circle?
• Piltz divisor problem, especially Dirichlet's divisor problem
• Exponent pair conjecture
• Is π a normal number (its digits are "random")?
• Casas-Alvero conjecture
• Sato–Tate conjecture
• Find value of De Bruijn–Newman constant
• Which integers can be written as the sum of three perfect cubes?
• Erdős–Moser problem: is 1 + 2 = 3 the only solution to the Erdős–Moser equation?
• Is there a covering system with odd distinct moduli?
• Singmaster's conjecture: is there a finite upper bound on the multiplicities of the entries greater than 1 in Pascal's triangle?
• The uniqueness conjecture for Markov numbers
• Keating–Snaith conjecture concerning the asymptotics of an integral involving the Riemann zeta function

Additive number theory

• Beal's conjecture
• Fermat–Catalan conjecture
• Goldbach's conjecture
• The values of g(k) and G(k) in Waring's problem
• Lander, Parkin, and Selfridge conjecture
• Gilbreath's conjecture
• Erdős conjecture on arithmetic progressions
• Erdős–Turán conjecture on additive bases
• Pollock octahedral numbers conjecture
• Skolem problem
• Determine growth rate of r_k(N) (see Szemerédi's theorem)
• Minimum overlap problem
• Do the Ulam numbers have a positive density?

Algebraic number theory

• Are there infinitely many real quadratic number fields with unique factorization (Class number problem)?
• Characterize all algebraic number fields that have some power basis.
• Stark conjectures (including Brumer–Stark conjecture)
• Kummer–Vandiver conjecture
• Greenberg's conjectures

Computational number theory

• Integer factorization: Can integer factorization be done in polynomial time?

Prime numbers

• Goldbach conjecture
• Twin prime conjecture
• Polignac's conjecture
• Brocard's Conjecture
• Catalan's Mersenne conjecture
• Agoh–Giuga conjecture
• Dubner's conjecture
• The Gaussian moat problem: is it possible to find an infinite sequence of distinct Gaussian prime numbers such that the difference between consecutive numbers in the sequence is bounded?
• New Mersenne conjecture
• Erdős–Mollin–Walsh conjecture
• Bunyakovsky conjecture
• Dickson's conjecture
• Schinzel's hypothesis H
• Are there infinitely many prime quadruplets?
• Are there infinitely many cousin primes?
• Are there infinitely many sexy primes?
• Are there infinitely many Mersenne primes (Lenstra–Pomerance–Wagstaff conjecture); equivalently, infinitely many even perfect numbers?
• Are there infinitely many Wagstaff primes?
• Are there infinitely many Sophie Germain primes?
• Are there infinitely many Pierpont primes?
• Are there infinitely many regular primes, and if so is their relative density ${\displaystyle e^{-1/2}}$?
• For any given integer b which is not a perfect power and not of the form −4k for integer k, are there infinitely many repunit primes to base b?
• Are there infinitely many Cullen primes?
• Are there infinitely many Woodall primes?
• Are there infinitely many Carol primes?
• Are there infinitely many Kynea primes?
• Are there infinitely many palindromic primes to every base?
• Are there infinitely many Fibonacci primes?
• Are there infinitely many Lucas primes?
• Are there infinitely many Pell primes?
• Are there infinitely many Newman–Shanks–Williams primes?
• Are all Mersenne numbers of prime index square-free?
• Are there infinitely many Wieferich primes?
• Are there any Wieferich primes in base 47?
• Are there any composite c satisfying 2 ≡ 1 (mod c)?
• For any given integer a > 0, are there infinitely many primes p such that a ≡ 1 (mod p)?
• Can a prime p satisfy 2 ≡ 1 (mod p) and 3 ≡ 1 (mod p) simultaneously?
• Are there infinitely many Wilson primes?
• Are there infinitely many Wolstenholme primes?
• Are there any Wall–Sun–Sun primes?
• For any given integer a > 0, are there infinitely many Lucas–Wieferich primes associated with the pair (a, −1)? (Specially, when a = 1, this is the Fibonacci-Wieferich primes, and when a = 2, this is the Pell-Wieferich primes)
• Is every Fermat number 2 + 1 composite for ${\displaystyle n>4}$?
• Are all Fermat numbers square-free?
• For any given integer a which is not a square and does not equal to −1, are there infinitely many primes with a as a primitive root?
• Artin's conjecture on primitive roots
• Is 78,557 the lowest Sierpiński number (so-called Selfridge's conjecture)?
• Is 509,203 the lowest Riesel number?
• For any given integers k ≥ 1, b ≥ 2, c ≠ 0, with gcd(k, c) = 1 and gcd(b, c) = 1, are there infinitely many primes of the form (k×b+c)/gcd(k+c,b−1) with integer n ≥ 1?
• Fortune's conjecture (that no Fortunate number is composite)
• Landau's problems
• Feit–Thompson conjecture
• Does every prime number appear in the Euclid–Mullin sequence?
• Does the converse of Wolstenholme's theorem hold for all natural numbers?
• Elliott–Halberstam conjecture
• Problems associated to Linnik's theorem
• Find the smallest Skewes' number

Set theory

• The problem of finding the ultimate core model, one that contains all large cardinals.
• If ℵ_ω is a strong limit cardinal, then 2 < ℵ_ω1 (see Singular cardinals hypothesis). The best bound, ℵ_ω4, was obtained by Shelah using his pcf theory.
• Woodin's Ω-hypothesis.
• Does the consistency of the existence of a strongly compact cardinal imply the consistent existence of a supercompact cardinal?
• (Woodin) Does the Generalized Continuum Hypothesis below a strongly compact cardinal imply the Generalized Continuum Hypothesis everywhere?
• Does there exist a Jónsson algebra on ℵ_ω?
• Without assuming the axiom of choice, can a nontrivial elementary embedding V→V exist?
• Does the Generalized Continuum Hypothesis entail ${\displaystyle {\diamondsuit (E_{\operatorname {cf} (\lambda )}^{\lambda ^{+}}})}$ for every singular cardinal ${\displaystyle \lambda }$?
• Does the Generalized Continuum Hypothesis imply the existence of an ℵ₂-Suslin tree?
• Is OCA (Open coloring axiom) consistent with ${\displaystyle 2^{\aleph _{0}}>\aleph _{2}}$?

Topology

• Baum–Connes conjecture
• Borel conjecture
• Hilbert–Smith conjecture
• Mazur's conjectures
• Novikov conjecture
• Telescope conjectures
• Unknotting problem
• Volume conjecture
• Whitehead conjecture
• Zeeman conjecture

Problems solved since 1995

Algebra

• Connes embedding problem (Zhengfeng Ji, Anand Natarajan, Thomas Vidick, John Wright, Henry Yuen, 2020)

Analysis

• Kadison–Singer problem (Adam Marcus, Daniel Spielman and Nikhil Srivastava, 2013) (and the Feichtinger's conjecture, Anderson’s paving conjectures, Weaver’s discrepancy theoretic ${\displaystyle KS_{r}}$ and ${\displaystyle KS'_{r}}$ conjectures, Bourgain-Tzafriri conjecture and ${\displaystyle R_{\epsilon }}$-conjecture)

Combinatorics

• Erdős sumset conjecture (Joel Moreira, Florian Richter, Donald Robertson, 2018)
• McMullen's g-conjecture on the possible numbers of faces of different dimensions in a simplicial sphere (also Grünbaum conjecture, several conjectures of Kühnel)(Karim Adiprasito, 2018)
• Hirsch conjecture (Francisco Santos Leal, 2010)

Game theory

• The angel problem (Various independent proofs, 2006)

Geometry

• Yau's conjecture (Antoine Song, 2018)
• Pentagonal tiling (Michaël Rao, 2017)
• Erdős distinct distances problem (Larry Guth, Netz Hawk Katz, 2011)
• Heterogeneous tiling conjecture (squaring the plane) (Frederick V. Henle and James M. Henle, 2008)

Graph theory

• Ringel's conjecture on graceful labeling of trees (Richard Montgomery, Benny Sudakov, Alexey Pokrovskiy, 2020)
• Hedetniemi's conjecture on the chromatic number of tensor products of graphs (Yaroslav Shitov, 2019)
• Babai's problem (Problem 3.3 in "Spectra of Cayley graphs") (Alireza Abdollahi, Maysam Zallaghi, 2015)
• Alspach's conjecture (Darryn Bryant, Daniel Horsley, William Pettersson, 2014)
• Scheinerman's conjecture (Jeremie Chalopin and Daniel Gonçalves, 2009)
• Erdős–Menger conjecture (Aharoni, Berger 2007)
• Road coloring conjecture (Avraham Trahtman, 2007)

Group theory

• Hanna Neumann conjecture (Mineyev, 2011)
• Density theorem (Namazi, Souto, 2010)
• Full classification of finite simple groups (Harada, Solomon, 2008)

Number theory

• Duffin-Schaeffer conjecture (Dimitris Koukoulopoulos, James Maynard, 2019)
• Main conjecture in Vinogradov's mean-value theorem (Jean Bourgain, Ciprian Demeter, Larry Guth, 2015)
• Goldbach's weak conjecture (Harald Helfgott, 2013)
• Serre's modularity conjecture (Chandrashekhar Khare and Jean-Pierre Wintenberger, 2008)

Ramsey theory

• Burr–Erdős conjecture (Choongbum Lee, 2017)
• Boolean Pythagorean triples problem (Marijn Heule, Oliver Kullmann, Victor Marek, 2016)

Topology

• Deciding whether the Conway knot is a slice knot (Lisa Piccirillo, 2020)
• Virtual Haken conjecture (Agol, Groves, Manning, 2012) (and by work of Wise also virtually fibered conjecture)
• Hsiang–Lawson's conjecture (Brendle, 2012)
• Ehrenpreis conjecture (Kahn, Markovic, 2011)
• Atiyah conjecture (Austin, 2009)
• Cobordism hypothesis (Jacob Lurie, 2008)
• Geometrization conjecture, proven by Grigori Perelman in a series of preprints in 2002–2003.
• Spherical space form conjecture (Grigori Perelman, 2006)

Uncategorised

• Erdős discrepancy problem (Terence Tao, 2015)
• Umbral moonshine conjecture (John F. R. Duncan, Michael J. Griffin, Ken Ono, 2015)
• Anderson conjecture (Cheeger, Naber, 2014)
• Gaussian correlation inequality (Thomas Royen, 2014)
• Willmore conjecture (Fernando Codá Marques and André Neves, 2012)
• Beck's 3-permutations conjecture (Newman, Nikolov, 2011)
• Bloch–Kato conjecture (Voevodsky, 2011) (and Quillen–Lichtenbaum conjecture and by work of Geisser and Levine (2001) also Beilinson–Lichtenbaum conjecture)
• Sidon set problem (J. Cilleruelo, I. Ruzsa and C. Vinuesa, 2010)
• Kauffman–Harary conjecture (Matmann, Solis, 2009)
• Surface subgroup conjecture (Kahn, Markovic, 2009)
• Normal scalar curvature conjecture and the Böttcher–Wenzel conjecture (Lu, 2007)
• Nirenberg–Treves conjecture (Nils Dencker, 2005)
• Lax conjecture (Lewis, Parrilo, Ramana, 2005)
• The Langlands–Shelstad fundamental lemma (Ngô Bảo Châu and Gérard Laumon, 2004)
• Tameness conjecture and Ahlfors measure conjecture (Ian Agol, 2004)
• Robertson–Seymour theorem (Robertson, Seymour, 2004)
• Stanley–Wilf conjecture (Gábor Tardos and Adam Marcus, 2004) (and also Alon–Friedgut conjecture)
• Green–Tao theorem (Ben J. Green and Terence Tao, 2004)
• Ending lamination theorem (Jeffrey F. Brock, Richard D. Canary, Yair N. Minsky, 2004)
• Carpenter's rule problem (Connelly, Demaine, Rote, 2003)
• Cameron–Erdős conjecture (Ben J. Green, 2003, Alexander Sapozhenko, 2003)
• Milnor conjecture (Vladimir Voevodsky, 2003)
• Kemnitz's conjecture (Reiher, 2003, di Fiore, 2003)
• Nagata's conjecture (Shestakov, Umirbaev, 2003)
• Kirillov's conjecture (Baruch, 2003)
• Poincaré conjecture (Grigori Perelman, 2002)
• Strong perfect graph conjecture (Maria Chudnovsky, Neil Robertson, Paul Seymour and Robin Thomas, 2002)
• Kouchnirenko’s conjecture (Haas, 2002)
• Vaught conjecture (Knight, 2002)
• Double bubble conjecture (Hutchings, Morgan, Ritoré, Ros, 2002)
• Catalan's conjecture (Preda Mihăilescu, 2002)
• n! conjecture (Haiman, 2001) (and also Macdonald positivity conjecture)
• Kato's conjecture (Auscher, Hofmann, Lacey, McIntosh and Tchamitchian, 2001)
• Deligne's conjecture on 1-motives (Luca Barbieri-Viale, Andreas Rosenschon, Morihiko Saito, 2001)
• Modularity theorem (Breuil, Conrad, Diamond and Taylor, 2001)
• Erdős–Stewart conjecture (Florian Luca, 2001)
• Berry–Robbins problem (Atiyah, 2000)
• Erdős–Graham problem (Croot, 2000)
• Honeycomb conjecture (Thomas Hales, 1999)
• Gradient conjecture (Krzysztof Kurdyka, Tadeusz Mostowski, Adam Parusinski, 1999)
• Bogomolov conjecture (Emmanuel Ullmo, 1998, Shou-Wu Zhang, 1998)
• Lafforgue's theorem (Laurent Lafforgue, 1998)
• Kepler conjecture (Ferguson, Hales, 1998)
• Dodecahedral conjecture (Hales, McLaughlin, 1998)
• Ganea conjecture (Iwase, 1997)
• Torsion conjecture (Merel, 1996)
• Harary's conjecture (Chen, 1996)
• Fermat's Last Theorem (Andrew Wiles and Richard Taylor, 1995)

See also

• List of conjectures
• List of unsolved problems in statistics
• List of unsolved problems in computer science
• List of unsolved problems in physics
• Lists of unsolved problems
• Open Problems in Mathematics
• The Great Mathematical Problems

References

1. Eves, An Introduction to the History of Mathematics 6th Edition, Thomson, 1990, ISBN 978-0-03-029558-4.
2. Thiele, Rüdiger (2005), "On Hilbert and his twenty-four problems", in Van Brummelen, Glen (ed.), Mathematics and the historian's craft. The Kenneth O. May Lectures, CMS Books in Mathematics/Ouvrages de Mathématiques de la SMC, vol. 21, pp. 243–295, ISBN 978-0-387-25284-1
3. Guy, Richard (1994), Unsolved Problems in Number Theory (2nd ed.), Springer, p. vii, ISBN 978-1-4899-3585-4, archived from the original on 2019-03-23, retrieved 2016-09-22.
4. Shimura, G. (1989). "Yutaka Taniyama and his time". Bulletin of the London Mathematical Society. 21 (2): 186–196. doi:10.1112/blms/21.2.186. Archived from the original on 2016-01-25. Retrieved 2015-01-15.
5. "Archived copy" (PDF). Archived from the original (PDF) on 2016-02-08. Retrieved 2016-01-22.{{cite web}}: CS1 maint: archived copy as title (link)
6. "THREE DIMENSIONAL MANIFOLDS, KLEINIAN GROUPS AND HYPERBOLIC GEOMETRY" (PDF). Archived (PDF) from the original on 2016-04-10. Retrieved 2016-02-09.
7. ^ "Millennium Problems". Archived from the original on 2017-06-06. Retrieved 2015-01-20.
8. "Fields Medal awarded to Artur Avila". Centre national de la recherche scientifique. 2014-08-13. Archived from the original on 2018-07-10. Retrieved 2018-07-07.
9. Bellos, Alex (2014-08-13). "Fields Medals 2014: the maths of Avila, Bhargava, Hairer and Mirzakhani explained". The Guardian. Archived from the original on 2016-10-21. Retrieved 2018-07-07.
10. Abe, Jair Minoro; Tanaka, Shotaro (2001). Unsolved Problems on Mathematics for the 21st Century. IOS Press. ISBN 978-9051994902.
11. "DARPA invests in math". CNN. 2008-10-14. Archived from the original on 2009-03-04. Retrieved 2013-01-14.
12. "Broad Agency Announcement (BAA 07-68) for Defense Sciences Office (DSO)". DARPA. 2007-09-10. Archived from the original on 2012-10-01. Retrieved 2013-06-25.
13. "Poincaré Conjecture". Clay Mathematics Institute. Archived from the original on 2013-12-15.
14. "Smooth 4-dimensional Poincare conjecture". Archived from the original on 2018-01-25. Retrieved 2019-08-06.
15. Dnestrovskaya notebook (PDF) (in Russian), The Russian Academy of Sciences, 1993
    "Dneister Notebook: Unsolved Problems in the Theory of Rings and Modules" (PDF), University of Saskatchewan, retrieved 2019-08-15
16. Erlagol notebook (PDF) (in Russian), The Novosibirsk State University, 2018
17. ^ Waldschmidt, Michel (2013), Diophantine Approximation on Linear Algebraic Groups: Transcendence Properties of the Exponential Function in Several Variables, Springer, pp. 14, 16, ISBN 9783662115695
18. Smyth, Chris (2008), "The Mahler measure of algebraic numbers: a survey", in McKee, James; Smyth, Chris (eds.), Number Theory and Polynomials, London Mathematical Society Lecture Note Series, vol. 352, Cambridge University Press, pp. 322–349, ISBN 978-0-521-71467-9
19. Berenstein, Carlos A. (2001) , "Pompeiu problem", Encyclopedia of Mathematics, EMS Press
20. For background on the numbers that are the focus of this problem, see articles by Eric W. Weisstein, on pi ( Archived 2014-12-06 at the Wayback Machine), e ( Archived 2014-11-21 at the Wayback Machine), Khinchin's Constant ( Archived 2014-11-05 at the Wayback Machine), irrational numbers ( Archived 2015-03-27 at the Wayback Machine), transcendental numbers ( Archived 2014-11-13 at the Wayback Machine), and irrationality measures ( Archived 2015-04-21 at the Wayback Machine) at Wolfram MathWorld, all articles accessed 15 December 2014.
21. Michel Waldschmidt, 2008, "An introduction to irrationality and transcendence methods," at The University of Arizona The Southwest Center for Arithmetic Geometry 2008 Arizona Winter School, March 15–19, 2008 (Special Functions and Transcendence), see Archived 2014-12-16 at the Wayback Machine, accessed 15 December 2014.
22. John Albert, posting date unknown, "Some unsolved problems in number theory" , in University of Oklahoma Math 4513 course materials, see Archived 2014-01-17 at the Wayback Machine, accessed 15 December 2014.
23. Kung, H. T.; Traub, Joseph Frederick (1974), "Optimal order of one-point and multipoint iteration", Journal of the ACM, 21 (4): 643–651, doi:10.1145/321850.321860, S2CID 74921
24. Bruhn, Henning; Schaudt, Oliver (2015), "The journey of the union-closed sets conjecture" (PDF), Graphs and Combinatorics, 31 (6): 2043–2074, arXiv:1309.3297, doi:10.1007/s00373-014-1515-0, MR 3417215, S2CID 17531822, archived (PDF) from the original on 2017-08-08, retrieved 2017-07-18
25. Tao, Terence (2017), "Some remarks on the lonely runner conjecture", arXiv:1701.02048
26. Liśkiewicz, Maciej; Ogihara, Mitsunori; Toda, Seinosuke (2003-07-28). "The complexity of counting self-avoiding walks in subgraphs of two-dimensional grids and hypercubes". Theoretical Computer Science. 304 (1): 129–156. doi:10.1016/S0304-3975(03)00080-X.
27. Brightwell, Graham R.; Felsner, Stefan; Trotter, William T. (1995), "Balancing pairs and the cross product conjecture", Order, 12 (4): 327–349, CiteSeerX 10.1.1.38.7841, doi:10.1007/BF01110378, MR 1368815, S2CID 14793475.
28. Murnaghan, F. D. (1938), "The Analysis of the Direct Product of Irreducible Representations of the Symmetric Groups", American Journal of Mathematics, 60 (1): 44–65, doi:10.2307/2371542, JSTOR 2371542, MR 1507301, PMC 1076971, PMID 16577800
29. Dedekind Numbers and Related Sequences
30. Kari, Jarkko (2009), "Structure of reversible cellular automata", Unconventional Computation: 8th International Conference, UC 2009, Ponta Delgada, Portugal, September 7ÔÇô11, 2009, Proceedings, Lecture Notes in Computer Science, vol. 5715, Springer, p. 6, Bibcode:2009LNCS.5715....6K, doi:10.1007/978-3-642-03745-0_5, ISBN 978-3-642-03744-3
31. Kaloshin, Vadim; Sorrentino, Alfonso (2018). "On the local Birkhoff conjecture for convex billiards". Annals of Mathematics. 188 (1): 315–380. arXiv:1612.09194. doi:10.4007/annals.2018.188.1.6. S2CID 119171182.
32. Sarnak, Peter (2011), "Recent progress on the quantum unique ergodicity conjecture", Bulletin of the American Mathematical Society, 48 (2): 211–228, doi:10.1090/S0273-0979-2011-01323-4, MR 2774090
33. ^ http://english.log-it-ex.com Archived 2017-11-10 at the Wayback Machine Ten open questions about Sudoku (2012-01-21).
34. "Higher-Dimensional Tic-Tac-Toe". PBS Infinite Series. YouTube. 2017-09-21. Archived from the original on 2017-10-11. Retrieved 2018-07-29.
35. Barlet, Daniel; Peternell, Thomas; Schneider, Michael (1990). "On two conjectures of Hartshorne's". Mathematische Annalen. 286 (1–3): 13–25. doi:10.1007/BF01453563. S2CID 122151259.
36. Maulik, Davesh; Nekrasov, Nikita; Okounov, Andrei; Pandharipande, Rahul (2004-06-05), Gromov–Witten theory and Donaldson–Thomas theory, I, arXiv:math/0312059, Bibcode:2003math.....12059M
37. Zariski, Oscar (1971). "Some open questions in the theory of singularities". Bulletin of the American Mathematical Society. 77 (4): 481–491. doi:10.1090/S0002-9904-1971-12729-5. MR 0277533.
38. Katz, Mikhail G. (2007), Systolic geometry and topology, Mathematical Surveys and Monographs, vol. 137, American Mathematical Society, Providence, RI, p. 57, doi:10.1090/surv/137, ISBN 978-0-8218-4177-8, MR 2292367
39. Rosenberg, Steven (1997), The Laplacian on a Riemannian Manifold: An introduction to analysis on manifolds, London Mathematical Society Student Texts, vol. 31, Cambridge: Cambridge University Press, pp. 62–63, doi:10.1017/CBO9780511623783, ISBN 978-0-521-46300-3, MR 1462892
40. Barros, Manuel (1997), "General Helices and a Theorem of Lancret", Proceedings of the American Mathematical Society, 125 (5): 1503–1509, doi:10.1090/S0002-9939-97-03692-7, JSTOR 2162098
41. Morris, Walter D.; Soltan, Valeriu (2000), "The Erdős-Szekeres problem on points in convex position—a survey", Bull. Amer. Math. Soc., 37 (4): 437–458, doi:10.1090/S0273-0979-00-00877-6, MR 1779413; Suk, Andrew (2016), "On the Erdős–Szekeres convex polygon problem", J. Amer. Math. Soc., 30 (4): 1047–1053, arXiv:1604.08657, doi:10.1090/jams/869, S2CID 15732134
42. Dey, Tamal K. (1998), "Improved bounds for planar k-sets and related problems", Discrete Comput. Geom., 19 (3): 373–382, doi:10.1007/PL00009354, MR 1608878; Tóth, Gábor (2001), "Point sets with many k-sets", Discrete Comput. Geom., 26 (2): 187–194, doi:10.1007/s004540010022, MR 1843435.
43. Boltjansky, V.; Gohberg, I. (1985), "11. Hadwiger's Conjecture", Results and Problems in Combinatorial Geometry, Cambridge University Press, pp. 44–46.
44. Weisstein, Eric W. "Kobon Triangle". MathWorld.
45. Matoušek, Jiří (2002), Lectures on discrete geometry, Graduate Texts in Mathematics, vol. 212, Springer-Verlag, New York, p. 206, doi:10.1007/978-1-4613-0039-7, ISBN 978-0-387-95373-1, MR 1899299
46. Aronov, Boris; Dujmović, Vida; Morin, Pat; Ooms, Aurélien; Schultz Xavier da Silveira, Luís Fernando (2019), "More Turán-type theorems for triangles in convex point sets", Electronic Journal of Combinatorics, 26 (1): P1.8, arXiv:1706.10193, Bibcode:2017arXiv170610193A, doi:10.37236/7224, archived from the original on 2019-02-18, retrieved 2019-02-18
47. Gardner, Martin (1995), New Mathematical Diversions (Revised Edition), Washington: Mathematical Association of America, p. 251
48. Brass, Peter; Moser, William; Pach, János (2005), Research Problems in Discrete Geometry, New York: Springer, p. 45, ISBN 978-0387-23815-9, MR 2163782
49. Conway, John H.; Neil J.A. Sloane (1999), Sphere Packings, Lattices and Groups (3rd ed.), New York: Springer-Verlag, pp. 21–22, ISBN 978-0-387-98585-5
50. Brass, Peter; Moser, William; Pach, János (2005), "5.1 The Maximum Number of Unit Distances in the Plane", Research problems in discrete geometry, Springer, New York, pp. 183–190, ISBN 978-0-387-23815-9, MR 2163782
51. Kalai, Gil (1989), "The number of faces of centrally-symmetric polytopes", Graphs and Combinatorics, 5 (1): 389–391, doi:10.1007/BF01788696, MR 1554357.
52. Finch, S. R.; Wetzel, J. E. (2004), "Lost in a forest", American Mathematical Monthly, 11 (8): 645–654, doi:10.2307/4145038, JSTOR 4145038, MR 2091541
53. Howards, Hugh Nelson (2013), "Forming the Borromean rings out of arbitrary polygonal unknots", Journal of Knot Theory and Its Ramifications, 22 (14): 1350083, 15, arXiv:1406.3370, doi:10.1142/S0218216513500831, MR 3190121, S2CID 119674622
54. Solomon, Yaar; Weiss, Barak (2016), "Dense forests and Danzer sets", Annales Scientifiques de l'École Normale Supérieure, 49 (5): 1053–1074, arXiv:1406.3807, doi:10.24033/asens.2303, MR 3581810, S2CID 672315; Conway, John H., Five $1,000 Problems (Update 2017) (PDF), On-Line Encyclopedia of Integer Sequences, archived (PDF) from the original on 2019-02-13, retrieved 2019-02-12
55. Brandts, Jan; Korotov, Sergey; Křížek, Michal; Šolc, Jakub (2009), "On nonobtuse simplicial partitions" (PDF), SIAM Review, 51 (2): 317–335, Bibcode:2009SIAMR..51..317B, doi:10.1137/060669073, MR 2505583, archived (PDF) from the original on 2018-11-04, retrieved 2018-11-22. See in particular Conjecture 23, p. 327.
56. Socolar, Joshua E. S.; Taylor, Joan M. (2012), "Forcing nonperiodicity with a single tile", The Mathematical Intelligencer, 34 (1): 18–28, arXiv:1009.1419, doi:10.1007/s00283-011-9255-y, MR 2902144, S2CID 10747746
57. Melissen, Hans (1993), "Densest packings of congruent circles in an equilateral triangle", American Mathematical Monthly, 100 (10): 916–925, doi:10.2307/2324212, JSTOR 2324212, MR 1252928
58. Arutyunyants, G.; Iosevich, A. (2004), "Falconer conjecture, spherical averages and discrete analogs", in Pach, János (ed.), Towards a Theory of Geometric Graphs, Contemp. Math., vol. 342, Amer. Math. Soc., Providence, RI, pp. 15–24, doi:10.1090/conm/342/06127, ISBN 9780821834848, MR 2065249
59. Matschke, Benjamin (2014), "A survey on the square peg problem", Notices of the American Mathematical Society, 61 (4): 346–352, doi:10.1090/noti1100
60. Katz, Nets; Tao, Terence (2002), "Recent progress on the Kakeya conjecture", Proceedings of the 6th International Conference on Harmonic Analysis and Partial Differential Equations (El Escorial, 2000), Publicacions Matemàtiques (Vol. Extra): 161–179, CiteSeerX 10.1.1.241.5335, doi:10.5565/PUBLMAT_Esco02_07, MR 1964819, S2CID 77088 {{citation}}: |issue= has extra text (help)
61. Weaire, Denis, ed. (1997), The Kelvin Problem, CRC Press, p. 1, ISBN 9780748406326
62. Brass, Peter; Moser, William; Pach, János (2005), Research problems in discrete geometry, New York: Springer, p. 457, ISBN 9780387299297, MR 2163782
63. Norwood, Rick; Poole, George; Laidacker, Michael (1992), "The worm problem of Leo Moser", Discrete and Computational Geometry, 7 (2): 153–162, doi:10.1007/BF02187832, MR 1139077
64. Wagner, Neal R. (1976), "The Sofa Problem" (PDF), The American Mathematical Monthly, 83 (3): 188–189, doi:10.2307/2977022, JSTOR 2977022, archived (PDF) from the original on 2015-04-20, retrieved 2014-05-14
65. Demaine, Erik D.; O'Rourke, Joseph (2007), "Chapter 22. Edge Unfolding of Polyhedra", Geometric Folding Algorithms: Linkages, Origami, Polyhedra, Cambridge University Press, pp. 306–338
66. Ghomi, Mohammad (2018-01-01). "D "urer's Unfolding Problem for Convex Polyhedra". Notices of the American Mathematical Society. 65 (1): 25–27. doi:10.1090/noti1609. ISSN 0002-9920.
67. Whyte, L. L. (1952), "Unique arrangements of points on a sphere", The American Mathematical Monthly, 59 (9): 606–611, doi:10.2307/2306764, JSTOR 2306764, MR 0050303
68. ACW (May 24, 2012), "Convex uniform 5-polytopes", Open Problem Garden, archived from the original on October 5, 2016, retrieved 2016-10-04.
69. Bereg, Sergey; Dumitrescu, Adrian; Jiang, Minghui (2010), "On covering problems of Rado", Algorithmica, 57 (3): 538–561, doi:10.1007/s00453-009-9298-z, MR 2609053, S2CID 6511998
70. Mahler, Kurt (1939). "Ein Minimalproblem für konvexe Polygone". Mathematica (Zutphen) B: 118–127.
71. Florek, Jan (2010), "On Barnette's conjecture", Discrete Mathematics, 310 (10–11): 1531–1535, doi:10.1016/j.disc.2010.01.018, MR 2601261.
72. Broersma, Hajo; Patel, Viresh; Pyatkin, Artem (2014), "On toughness and Hamiltonicity of $2K_2$-free graphs", Journal of Graph Theory, 75 (3): 244–255, doi:10.1002/jgt.21734, MR 3153119
73. Jaeger, F. (1985), "A survey of the cycle double cover conjecture", Annals of Discrete Mathematics 27 – Cycles in Graphs, North-Holland Mathematics Studies, vol. 27, pp. 1–12, doi:10.1016/S0304-0208(08)72993-1, ISBN 9780444878038.
74. Heckman, Christopher Carl; Krakovski, Roi (2013), "Erdös-Gyárfás conjecture for cubic planar graphs", Electronic Journal of Combinatorics, 20 (2), P7, doi:10.37236/3252.
75. Akiyama, Jin; Exoo, Geoffrey; Harary, Frank (1981), "Covering and packing in graphs. IV. Linear arboricity", Networks, 11 (1): 69–72, doi:10.1002/net.3230110108, MR 0608921.
76. L. Babai, Automorphism groups, isomorphism, reconstruction Archived 2007-06-13 at the Wayback Machine, in Handbook of Combinatorics, Vol. 2, Elsevier, 1996, 1447–1540.
77. Lenz, Hanfried; Ringel, Gerhard (1991), "A brief review on Egmont Köhler's mathematical work", Discrete Mathematics, 97 (1–3): 3–16, doi:10.1016/0012-365X(91)90416-Y, MR 1140782
78. Bousquet, Nicolas; Bartier, Valentin (2019), "Linear Transformations Between Colorings in Chordal Graphs", in Bender, Michael A.; Svensson, Ola; Herman, Grzegorz (eds.), 27th Annual European Symposium on Algorithms, ESA 2019, September 9-11, 2019, Munich/Garching, Germany, LIPIcs, vol. 144, Schloss Dagstuhl - Leibniz-Zentrum für Informatik, pp. 24:1–24:15, doi:10.4230/LIPIcs.ESA.2019.24, S2CID 195791634{{citation}}: CS1 maint: unflagged free DOI (link)
79. Chung, Fan; Graham, Ron (1998), Erdős on Graphs: His Legacy of Unsolved Problems, A K Peters, pp. 97–99.
80. Chudnovsky, Maria; Seymour, Paul (2014), "Extending the Gyárfás-Sumner conjecture", Journal of Combinatorial Theory, Series B, 105: 11–16, doi:10.1016/j.jctb.2013.11.002, MR 3171779
81. Toft, Bjarne (1996), "A survey of Hadwiger's conjecture", Congressus Numerantium, 115: 249–283, MR 1411244.
82. Croft, Hallard T.; Falconer, Kenneth J.; Guy, Richard K. (1991), Unsolved Problems in Geometry, Springer-Verlag, Problem G10.
83. Hägglund, Jonas; Steffen, Eckhard (2014), "Petersen-colorings and some families of snarks", Ars Mathematica Contemporanea, 7 (1): 161–173, doi:10.26493/1855-3974.288.11a, MR 3047618, archived from the original on 2016-10-03, retrieved 2016-09-30.
84. Jensen, Tommy R.; Toft, Bjarne (1995), "12.20 List-Edge-Chromatic Numbers", Graph Coloring Problems, New York: Wiley-Interscience, pp. 201–202, ISBN 978-0-471-02865-9.
85. Molloy, Michael; Reed, Bruce (1998), "A bound on the total chromatic number", Combinatorica, 18 (2): 241–280, CiteSeerX 10.1.1.24.6514, doi:10.1007/PL00009820, MR 1656544, S2CID 9600550.
86. Barát, János; Tóth, Géza (2010), "Towards the Albertson Conjecture", Electronic Journal of Combinatorics, 17 (1): R73, arXiv:0909.0413, Bibcode:2009arXiv0909.0413B, doi:10.37236/345.
87. Wood, David (January 19, 2009), "Book Thickness of Subdivisions", Open Problem Garden, archived from the original on September 16, 2013, retrieved 2013-02-05.
88. Fulek, R.; Pach, J. (2011), "A computational approach to Conway's thrackle conjecture", Computational Geometry, 44 (6–7): 345–355, arXiv:1002.3904, doi:10.1007/978-3-642-18469-7_21, MR 2785903.
89. Hartsfield, Nora; Ringel, Gerhard (2013), Pearls in Graph Theory: A Comprehensive Introduction, Dover Books on Mathematics, Courier Dover Publications, p. 247, ISBN 978-0-486-31552-2, MR 2047103.
90. Hliněný, Petr (2010), "20 years of Negami's planar cover conjecture" (PDF), Graphs and Combinatorics, 26 (4): 525–536, CiteSeerX 10.1.1.605.4932, doi:10.1007/s00373-010-0934-9, MR 2669457, S2CID 121645, archived (PDF) from the original on 2016-03-04, retrieved 2016-10-04.
91. Nöllenburg, Martin; Prutkin, Roman; Rutter, Ignaz (2016), "On self-approaching and increasing-chord drawings of 3-connected planar graphs", Journal of Computational Geometry, 7 (1): 47–69, arXiv:1409.0315, doi:10.20382/jocg.v7i1a3, MR 3463906
92. Pach, János; Sharir, Micha (2009), "5.1 Crossings—the Brick Factory Problem", Combinatorial Geometry and Its Algorithmic Applications: The Alcalá Lectures, Mathematical Surveys and Monographs, vol. 152, American Mathematical Society, pp. 126–127.
93. Demaine, E.; O'Rourke, J. (2002–2012), "Problem 45: Smallest Universal Set of Points for Planar Graphs", The Open Problems Project, archived from the original on 2012-08-14, retrieved 2013-03-19.
94. ^ S. Kitaev and V. Lozin. Words and Graphs, Springer, 2015.
95. ^ S. Kitaev. A comprehensive introduction to the theory of word-representable graphs. In: É. Charlier, J. Leroy, M. Rigo (eds), Developments in Language Theory. DLT 2017. Lecture Notes Comp. Sci. 10396, Springer, 36−67.
96. ^ S. Kitaev and A. Pyatkin. Word-representable graphs: a Survey, Journal of Applied and Industrial Mathematics 12(2) (2018) 278−296.
97. ^ С. В. Китаев, А. В. Пяткин. Графы, представимые в виде слов. Обзор результатов, Дискретн. анализ и исслед. опер., 2018, том 25,номер 2, 19−53
98. Marc Elliot Glen (2016). "Colourability and word-representability of near-triangulations". arXiv:1605.01688 .
99. S. Kitaev. On graphs with representation number 3, J. Autom., Lang. and Combin. 18 (2013), 97−112.
100. Glen, Marc; Kitaev, Sergey; Pyatkin, Artem (2018). "On the representation number of a crown graph". Discrete Applied Mathematics. 244: 89–93. doi:10.1016/j.dam.2018.03.013. S2CID 46925617.
101. Conway, John H., Five $1,000 Problems (Update 2017) (PDF), Online Encyclopedia of Integer Sequences, archived (PDF) from the original on 2019-02-13, retrieved 2019-02-12
102. Chudnovsky, Maria (2014), "The Erdös–Hajnal conjecture—a survey" (PDF), Journal of Graph Theory, 75 (2): 178–190, arXiv:1606.08827, doi:10.1002/jgt.21730, MR 3150572, S2CID 985458, Zbl 1280.05086, archived (PDF) from the original on 2016-03-04, retrieved 2016-09-22.
103. Gupta, Anupam; Newman, Ilan; Rabinovich, Yuri; Sinclair, Alistair (2004), "Cuts, trees and ${\displaystyle \ell _{1}}$-embeddings of graphs", Combinatorica, 24 (2): 233–269, CiteSeerX 10.1.1.698.8978, doi:10.1007/s00493-004-0015-x, MR 2071334, S2CID 46133408
104. Pleanmani, Nopparat (2019), "Graham's pebbling conjecture holds for the product of a graph and a sufficiently large complete bipartite graph", Discrete Mathematics, Algorithms and Applications, 11 (6): 1950068, 7, doi:10.1142/s179383091950068x, MR 4044549
105. Spinrad, Jeremy P. (2003), "2. Implicit graph representation", Efficient Graph Representations, pp. 17–30, ISBN 978-0-8218-2815-1.
106. "Jorgensen's Conjecture", Open Problem Garden, archived from the original on 2016-11-14, retrieved 2016-11-13.
107. Baird, William; Bonato, Anthony (2012), "Meyniel's conjecture on the cop number: a survey", Journal of Combinatorics, 3 (2): 225–238, arXiv:1308.3385, doi:10.4310/JOC.2012.v3.n2.a6, MR 2980752, S2CID 18942362
108. Ducey, Joshua E. (2017), "On the critical group of the missing Moore graph", Discrete Mathematics, 340 (5): 1104–1109, arXiv:1509.00327, doi:10.1016/j.disc.2016.10.001, MR 3612450, S2CID 28297244
109. Fomin, Fedor V.; Høie, Kjartan (2006), "Pathwidth of cubic graphs and exact algorithms", Information Processing Letters, 97 (5): 191–196, doi:10.1016/j.ipl.2005.10.012, MR 2195217
110. Schwenk, Allen (2012), "Some History on the Reconstruction Conjecture" (PDF), Joint Mathematics Meetings, archived (PDF) from the original on 2015-04-09, retrieved 2018-11-26
111. Ramachandran, S. (1981), "On a new digraph reconstruction conjecture", Journal of Combinatorial Theory, Series B, 31 (2): 143–149, doi:10.1016/S0095-8956(81)80019-6, MR 0630977
112. Seymour's 2nd Neighborhood Conjecture Archived 2019-01-11 at the Wayback Machine, Open Problems in Graph Theory and Combinatorics, Douglas B. West.
113. Blokhuis, A.; Brouwer, A. E. (1988), "Geodetic graphs of diameter two", Geometriae Dedicata, 25 (1–3): 527–533, doi:10.1007/BF00191941, MR 0925851, S2CID 189890651
114. Kühn, Daniela; Mycroft, Richard; Osthus, Deryk (2011), "A proof of Sumner's universal tournament conjecture for large tournaments", Proceedings of the London Mathematical Society, Third Series, 102 (4): 731–766, arXiv:1010.4430, doi:10.1112/plms/pdq035, MR 2793448, S2CID 119169562, Zbl 1218.05034.
115. 4-flow conjecture Archived 2018-11-26 at the Wayback Machine and 5-flow conjecture Archived 2018-11-26 at the Wayback Machine, Open Problem Garden
116. Brešar, Boštjan; Dorbec, Paul; Goddard, Wayne; Hartnell, Bert L.; Henning, Michael A.; Klavžar, Sandi; Rall, Douglas F. (2012), "Vizing's conjecture: a survey and recent results", Journal of Graph Theory, 69 (1): 46–76, CiteSeerX 10.1.1.159.7029, doi:10.1002/jgt.20565, MR 2864622.
117. Aschbacher, Michael (1990), "On Conjectures of Guralnick and Thompson", Journal of Algebra, 135 (2): 277–343, doi:10.1016/0021-8693(90)90292-V
118. Khukhro, Evgeny I.; Mazurov, Victor D. (2019), Unsolved Problems in Group Theory. The Kourovka Notebook, arXiv:1401.0300v16
119. ^ Shelah S, Classification Theory, North-Holland, 1990
120. Keisler, HJ (1967). "Ultraproducts which are not saturated". J. Symb. Log. 32 (1): 23–46. doi:10.2307/2271240. JSTOR 2271240.
121. Malliaris M, Shelah S, "A dividing line in simple unstable theories." https://arxiv.org/abs/1208.2140 Archived 2017-08-02 at the Wayback Machine
122. Gurevich, Yuri, "Monadic Second-Order Theories," in J. Barwise, S. Feferman, eds., Model-Theoretic Logics (New York: Springer-Verlag, 1985), 479–506.
123. Peretz, Assaf (2006). "Geometry of forking in simple theories". Journal of Symbolic Logic. 71 (1): 347–359. arXiv:math/0412356. doi:10.2178/jsl/1140641179. S2CID 9380215.
124. Shelah, Saharon (1999). "Borel sets with large squares". Fundamenta Mathematicae. 159 (1): 1–50. arXiv:math/9802134. Bibcode:1998math......2134S. doi:10.4064/fm-159-1-1-50. S2CID 8846429.
125. Shelah, Saharon (2009). Classification theory for abstract elementary classes. College Publications. ISBN 978-1-904987-71-0.
126. Makowsky J, "Compactness, embeddings and definability," in Model-Theoretic Logics, eds Barwise and Feferman, Springer 1985 pps. 645–715.
127. Baldwin, John T. (July 24, 2009). Categoricity (PDF). American Mathematical Society. ISBN 978-0-8218-4893-7. Archived (PDF) from the original on July 29, 2010. Retrieved February 20, 2014.
128. Shelah, Saharon (2009). "Introduction to classification theory for abstract elementary classes". arXiv:0903.3428. Bibcode:2009arXiv0903.3428S. {{cite journal}}: Cite journal requires |journal= (help)
129. Hrushovski, Ehud (1989). "Kueker's conjecture for stable theories". Journal of Symbolic Logic. 54 (1): 207–220. doi:10.2307/2275025. JSTOR 2275025.
130. Cherlin, G.; Shelah, S. (May 2007). "Universal graphs with a forbidden subtree". Journal of Combinatorial Theory, Series B. 97 (3): 293–333. arXiv:math/0512218. doi:10.1016/j.jctb.2006.05.008. S2CID 10425739.
131. Džamonja, Mirna, "Club guessing and the universal models." On PCF, ed. M. Foreman, (Banff, Alberta, 2004).
132. "Are the Digits of Pi Random? Berkeley Lab Researcher May Hold Key". Archived from the original on 2016-03-27. Retrieved 2016-03-18.
133. Bruhn, Henning; Schaudt, Oliver (2016). "Newer sums of three cubes". arXiv:1604.07746v1 .
134. Guo, Song; Sun, Zhi-Wei (2005), "On odd covering systems with distinct moduli", Advances in Applied Mathematics, 35 (2): 182–187, arXiv:math/0412217, doi:10.1016/j.aam.2005.01.004, MR 2152886, S2CID 835158
135. Singmaster, D. (1971), "Research Problems: How often does an integer occur as a binomial coefficient?", American Mathematical Monthly, 78 (4): 385–386, doi:10.2307/2316907, JSTOR 2316907, MR 1536288.
136. Aigner, Martin (2013), Markov's theorem and 100 years of the uniqueness conjecture, Cham: Springer, doi:10.1007/978-3-319-00888-2, ISBN 978-3-319-00887-5, MR 3098784
137. Conrey, Brian (2016), "Lectures on the Riemann zeta function (book review)", Bulletin of the American Mathematical Society, 53 (3): 507–512, doi:10.1090/bull/1525
138. Ribenboim, P. (2006). Die Welt der Primzahlen. Springer-Lehrbuch (in German) (2nd ed.). Springer. pp. 242–243. doi:10.1007/978-3-642-18079-8. ISBN 978-3-642-18078-1.
139. Dobson, J. B. (1 April 2017), "On Lerch's formula for the Fermat quotient", p. 23, arXiv:1103.3907v6
140. Mazur, Barry (1992), "The topology of rational points", Experimental Mathematics, 1 (1): 35–45, doi:10.1080/10586458.1992.10504244 (inactive 2020-10-26), archived from the original on 2019-04-07, retrieved 2019-04-07{{citation}}: CS1 maint: DOI inactive as of October 2020 (link)
141. Casazza, Peter G.; Fickus, Matthew; Tremain, Janet C.; Weber, Eric (2006). "The Kadison-Singer problem in mathematics and engineering: A detailed account". In Han, Deguang; Jorgensen, Palle E. T.; Larson, David Royal (eds.). Large Deviations for Additive Functionals of Markov Chains: The 25th Great Plains Operator Theory Symposium, June 7–12, 2005, University of Central Florida, Florida. Contemporary Mathematics. Vol. 414. American Mathematical Society. pp. 299–355. doi:10.1090/conm/414/07820. ISBN 978-0-8218-3923-2. Retrieved 24 April 2015.
142. Mackenzie, Dana. "Kadison–Singer Problem Solved" (PDF). SIAM News. No. January/February 2014. Society for Industrial and Applied Mathematics. Archived (PDF) from the original on 23 October 2014. Retrieved 24 April 2015.
143. Moreira, Joel; Richter, Florian K.; Robertson, Donald (2019). "A proof of a sumset conjecture of Erdős". Annals of Mathematics. 189 (2): 605–652. arXiv:1803.00498. doi:10.4007/annals.2019.189.2.4. S2CID 119158401.
144. Stanley, Richard P. (1994), "A survey of Eulerian posets", in Bisztriczky, T.; McMullen, P.; Schneider, R.; Weiss, A. Ivić (eds.), Polytopes: abstract, convex and computational (Scarborough, ON, 1993), NATO Advanced Science Institutes Series C: Mathematical and Physical Sciences, vol. 440, Dordrecht: Kluwer Academic Publishers, pp. 301–333, MR 1322068. See in particular p. 316.
145. Kalai, Gil (2018-12-25). "Amazing: Karim Adiprasito proved the g-conjecture for spheres!". Archived from the original on 2019-02-16. Retrieved 2019-02-15.
146. Santos, Franciscos (2012). "A counterexample to the Hirsch conjecture". Annals of Mathematics. 176 (1): 383–412. arXiv:1006.2814. doi:10.4007/annals.2012.176.1.7. S2CID 15325169.
147. Ziegler, Günter M. (2012). "Who solved the Hirsch conjecture?". Documenta Mathematica. Extra Volume "Optimization Stories": 75–85. Archived from the original on 2015-04-02. Retrieved 2015-03-25.
148. "Archived copy" (PDF). Archived (PDF) from the original on 2016-03-04. Retrieved 2016-03-18.{{cite web}}: CS1 maint: archived copy as title (link)
149. "Archived copy" (PDF). Archived from the original (PDF) on 2016-01-07. Retrieved 2016-03-18.{{cite web}}: CS1 maint: archived copy as title (link)
150. "Archived copy" (PDF). Archived (PDF) from the original on 2016-10-13. Retrieved 2016-03-18.{{cite web}}: CS1 maint: archived copy as title (link)
151. "Archived copy" (PDF). Archived (PDF) from the original on 2016-03-04. Retrieved 2016-03-18.{{cite web}}: CS1 maint: archived copy as title (link)
152. https://www.claymath.org/people/antoine-song
153. Wolchover, Natalie (July 11, 2017), "Pentagon Tiling Proof Solves Century-Old Math Problem", Quanta Magazine, archived from the original on August 6, 2017, retrieved July 18, 2017
154. Bruhn, Henning; Schaudt, Oliver (2010). "On the Erdos distinct distance problem in the plane". arXiv:1011.4105v3 .
155. "Archived copy" (PDF). Archived (PDF) from the original on 2016-03-24. Retrieved 2016-03-18.{{cite web}}: CS1 maint: archived copy as title (link)
156. Huang, C.; Kotzig, A.; Rosa, A. (1982), "Further results on tree labellings", Utilitas Mathematica, 21: 31–48, MR 0668845.
157. Hartnett, Kevin. "Rainbow Proof Shows Graphs Have Uniform Parts". Quanta Magazine. Retrieved 2020-02-29.
158. Shitov, Yaroslav (May 2019). "Counterexamples to Hedetniemi's conjecture". arXiv:1905.02167 .
159. Abdollahi A., Zallaghi M. (2015). "Character sums for Cayley graphs". Communications in Algebra. 43 (12): 5159–5167. doi:10.1080/00927872.2014.967398. S2CID 117651702.
160. "Archived copy" (PDF). Archived from the original (PDF) on 2016-03-03. Retrieved 2016-03-18.{{cite web}}: CS1 maint: archived copy as title (link)
161. Bruhn, Henning; Schaudt, Oliver (2005). "Menger's theorem for infinite graphs". arXiv:math/0509397.
162. Seigel-Itzkovich, Judy (2008-02-08). "Russian immigrant solves math puzzle". The Jerusalem Post. Retrieved 2015-11-12.
163. "Archived copy" (PDF). Archived (PDF) from the original on 2016-10-07. Retrieved 2016-03-18.{{cite web}}: CS1 maint: archived copy as title (link)
164. Namazi, Hossein; Souto, Juan (2012). "Non-realizability and ending laminations: Proof of the density conjecture". Acta Mathematica. 209 (2): 323–395. doi:10.1007/s11511-012-0088-0.
165. Bourgain, Jean; Ciprian, Demeter; Larry, Guth (2015). "Proof of the main conjecture in Vinogradov's Mean Value Theorem for degrees higher than three". Annals of Mathematics. 184 (2): 633–682. arXiv:1512.01565. Bibcode:2015arXiv151201565B. doi:10.4007/annals.2016.184.2.7. hdl:1721.1/115568. S2CID 43929329.
166. Helfgott, Harald A. (2013). "Major arcs for Goldbach's theorem". arXiv:1305.2897 .
167. Helfgott, Harald A. (2012). "Minor arcs for Goldbach's problem". arXiv:1205.5252 .
168. Helfgott, Harald A. (2013). "The ternary Goldbach conjecture is true". arXiv:1312.7748 .
169. Khare, Chandrashekhar; Wintenberger, Jean-Pierre (2009), "Serre's modularity conjecture (I)", Inventiones Mathematicae, 178 (3): 485–504, Bibcode:2009InMat.178..485K, CiteSeerX 10.1.1.518.4611, doi:10.1007/s00222-009-0205-7, S2CID 14846347
170. Khare, Chandrashekhar; Wintenberger, Jean-Pierre (2009), "Serre's modularity conjecture (II)", Inventiones Mathematicae, 178 (3): 505–586, Bibcode:2009InMat.178..505K, CiteSeerX 10.1.1.228.8022, doi:10.1007/s00222-009-0206-6, S2CID 189820189
171. "2011 Cole Prize in Number Theory" (PDF). Notices of the AMS. 58 (4): 610–611. ISSN 1088-9477. OCLC 34550461. Archived (PDF) from the original on 2015-11-06. Retrieved 2015-11-12.
172. Lee, Choongbum (2017). "Ramsey numbers of degenerate graphs". Annals of Mathematics. 185 (3): 791–829. arXiv:1505.04773. doi:10.4007/annals.2017.185.3.2. S2CID 7974973.
173. Lamb, Evelyn (26 May 2016). "Two-hundred-terabyte maths proof is largest ever". Nature. 534 (7605): 17–18. Bibcode:2016Natur.534...17L. doi:10.1038/nature.2016.19990. PMID 27251254.
174. Heule, Marijn J. H.; Kullmann, Oliver; Marek, Victor W. (2016). "Solving and Verifying the Boolean Pythagorean Triples Problem via Cube-and-Conquer". In Creignou, N.; Le Berre, D. (eds.). Theory and Applications of Satisfiability Testing – SAT 2016. Lecture Notes in Computer Science. Vol. 9710. Springer, . pp. 228–245. arXiv:1605.00723. doi:10.1007/978-3-319-40970-2_15. ISBN 978-3-319-40969-6. MR 3534782. S2CID 7912943.
175. The Conway knot is not slice, Annals of Mathematics, volume 191, issue 2, pp. 581–591
176. Graduate Student Solves Decades-Old Conway Knot Problem, Quanta Magazine 19 May 2020
177. Bruhn, Henning; Schaudt, Oliver (2012). "The virtual Haken conjecture". arXiv:1204.2810v1 .
178. Lee, Choongbum (2012). "Embedded minimal tori in S^3 and the Lawson conjecture". arXiv:1203.6597v2 .
179. Bruhn, Henning; Schaudt, Oliver (2011). "The good pants homology and the Ehrenpreis conjecture". arXiv:1101.1330v4 .
180. Bruhn, Henning; Schaudt, Oliver (2009). "Rational group ring elements with kernels having irrational dimension". Proceedings of the London Mathematical Society. 107 (6): 1424–1448. arXiv:0909.2360. Bibcode:2009arXiv0909.2360A. doi:10.1112/plms/pdt029. S2CID 115160094.
181. Lurie, Jacob (2009). "On the classification of topological field theories". Current Developments in Mathematics. 2008: 129–280. arXiv:0905.0465. Bibcode:2009arXiv0905.0465L. doi:10.4310/cdm.2008.v2008.n1.a3. S2CID 115162503.
182. ^ "Prize for Resolution of the Poincaré Conjecture Awarded to Dr. Grigoriy Perelman" (PDF) (Press release). Clay Mathematics Institute. March 18, 2010. Archived from the original on March 22, 2010. Retrieved November 13, 2015. The Clay Mathematics Institute hereby awards the Millennium Prize for resolution of the Poincaré conjecture to Grigoriy Perelman.
183. Bruhn, Henning; Schaudt, Oliver (2008). "Completion of the Proof of the Geometrization Conjecture". arXiv:0809.4040 .
184. Bruhn, Henning; Schaudt, Oliver (2015). "The Erdos discrepancy problem". arXiv:1509.05363v5 .
185. Duncan, John F. R.; Griffin, Michael J.; Ono, Ken (1 December 2015). "Proof of the umbral moonshine conjecture". Research in the Mathematical Sciences. 2 (1): 26. arXiv:1503.01472. Bibcode:2015arXiv150301472D. doi:10.1186/s40687-015-0044-7. S2CID 43589605.{{cite journal}}: CS1 maint: unflagged free DOI (link)
186. Bruhn, Henning; Schaudt, Oliver (2014). "Regularity of Einstein Manifolds and the Codimension 4 Conjecture". arXiv:1406.6534v10 .
187. "A Long-Sought Proof, Found and Almost Lost". Quanta Magazine. Natalie Wolchover. March 28, 2017. Archived from the original on April 24, 2017. Retrieved May 2, 2017.
188. Marques, Fernando C.; Neves, André (2013). "Min-max theory and the Willmore conjecture". Annals of Mathematics. 179 (2): 683–782. arXiv:1202.6036. doi:10.4007/annals.2014.179.2.6. S2CID 50742102.
189. Lee, Choongbum (2011). "A counterexample to Beck's conjecture on the discrepancy of three permutations". arXiv:1104.2922 .
190. "Archived copy" (PDF). Archived (PDF) from the original on 2016-03-27. Retrieved 2016-03-18.{{cite web}}: CS1 maint: archived copy as title (link)
191. "Archived copy" (PDF). Archived (PDF) from the original on 2016-10-07. Retrieved 2016-03-18.{{cite web}}: CS1 maint: archived copy as title (link)
192. "page 359" (PDF). Archived (PDF) from the original on 2016-03-27. Retrieved 2016-03-18.
193. "motivic cohomology – Milnor–Bloch–Kato conjecture implies the Beilinson-Lichtenbaum conjecture – MathOverflow". Retrieved 2016-03-18.
194. Cilleruelo, Javier (2010). "Generalized Sidon sets". Advances in Mathematics. 225 (5): 2786–2807. doi:10.1016/j.aim.2010.05.010. hdl:10261/31032. S2CID 7385280.
195. Bruhn, Henning; Schaudt, Oliver (2009). "A proof of the Kauffman-Harary Conjecture". Algebr. Geom. Topol. 9 (4): 2027–2039. arXiv:0906.1612. Bibcode:2009arXiv0906.1612M. doi:10.2140/agt.2009.9.2027. S2CID 8447495.
196. Bruhn, Henning; Schaudt, Oliver (2009). "Immersing almost geodesic surfaces in a closed hyperbolic three manifold". arXiv:0910.5501v5 .
197. Lu, Zhiqin (2007). "Proof of the normal scalar curvature conjecture". arXiv:0711.3510 .
198. Dencker, Nils (2006), "The resolution of the Nirenberg–Treves conjecture" (PDF), Annals of Mathematics, 163 (2): 405–444, doi:10.4007/annals.2006.163.405, S2CID 16630732, archived (PDF) from the original on 2018-07-20, retrieved 2019-04-07
199. "Research Awards", Clay Mathematics Institute, archived from the original on 2019-04-07, retrieved 2019-04-07
200. "Archived copy" (PDF). Archived (PDF) from the original on 2016-04-06. Retrieved 2016-03-22.{{cite web}}: CS1 maint: archived copy as title (link)
201. "Fields Medal – Ngô Bảo Châu". International Congress of Mathematicians 2010. ICM. 19 August 2010. Archived from the original on 24 September 2015. Retrieved 2015-11-12. Ngô Bảo Châu is being awarded the 2010 Fields Medal for his proof of the Fundamental Lemma in the theory of automorphic forms through the introduction of new algebro-geometric methods.
202. Bruhn, Henning; Schaudt, Oliver (2004). "Tameness of hyperbolic 3-manifolds". arXiv:math/0405568.
203. "Graph Theory". Archived from the original on 2016-03-08. Retrieved 2016-03-18.
204. Chung, Fan; Greene, Curtis; Hutchinson, Joan (April 2015). "Herbert S. Wilf (1931–2012)". Notices of the AMS. 62 (4): 358. doi:10.1090/noti1247. ISSN 1088-9477. OCLC 34550461. The conjecture was finally given an exceptionally elegant proof by A. Marcus and G. Tardos in 2004.
205. "Bombieri and Tao Receive King Faisal Prize" (PDF). Notices of the AMS. 57 (5): 642–643. May 2010. ISSN 1088-9477. OCLC 34550461. Archived (PDF) from the original on 2016-03-04. Retrieved 2016-03-18. Working with Ben Green, he proved there are arbitrarily long arithmetic progressions of prime numbers—a result now known as the Green–Tao theorem.
206. Bruhn, Henning; Schaudt, Oliver (2004). "The classification of Kleinian surface groups, II: The Ending Lamination Conjecture". arXiv:math/0412006.
207. Connelly, Robert; Demaine, Erik D.; Rote, Günter (2003), "Straightening polygonal arcs and convexifying polygonal cycles" (PDF), Discrete and Computational Geometry, 30 (2): 205–239, doi:10.1007/s00454-003-0006-7, MR 1931840, S2CID 40382145
208. Green, Ben (2004), "The Cameron–Erdős conjecture", The Bulletin of the London Mathematical Society, 36 (6): 769–778, arXiv:math.NT/0304058, doi:10.1112/S0024609304003650, MR 2083752, S2CID 119615076
209. "News from 2007". American Mathematical Society. AMS. 31 December 2007. Archived from the original on 17 November 2015. Retrieved 2015-11-13. The 2007 prize also recognizes Green for "his many outstanding results including his resolution of the Cameron-Erdős conjecture..."
210. Voevodsky, Vladimir (2003). "Reduced power operations in motivic cohomology" (PDF). Publications Mathématiques de l'IHÉS. 98: 1–57. arXiv:math/0107109. CiteSeerX 10.1.1.170.4427. doi:10.1007/s10240-003-0009-z. S2CID 8172797. Archived from the original on 2017-07-28. Retrieved 2016-03-18.
211. Savchev, Svetoslav (2005). "Kemnitz' conjecture revisited". Discrete Mathematics. 297 (1–3): 196–201. doi:10.1016/j.disc.2005.02.018.
212. "Archived copy" (PDF). Archived (PDF) from the original on 2016-03-08. Retrieved 2016-03-23.{{cite web}}: CS1 maint: archived copy as title (link)
213. "Archived copy" (PDF). Archived (PDF) from the original on 2016-04-03. Retrieved 2016-03-20.{{cite web}}: CS1 maint: archived copy as title (link)
214. Chudnovsky, Maria; Robertson, Neil; Seymour, Paul; Thomas, Robin (2002). "The strong perfect graph theorem". arXiv:math/0212070. {{cite arXiv}}: Unknown parameter |url= ignored (help)
215. "Archived copy" (PDF). Archived (PDF) from the original on 2016-10-07. Retrieved 2016-03-18.{{cite web}}: CS1 maint: archived copy as title (link)
216. Knight, R. W. (2002), The Vaught Conjecture: A Counterexample, manuscript
217. "Archived copy" (PDF). Archived (PDF) from the original on 2016-03-03. Retrieved 2016-03-22.{{cite web}}: CS1 maint: archived copy as title (link)
218. Metsänkylä, Tauno (5 September 2003). "Catalan's conjecture: another old diophantine problem solved" (PDF). Bulletin of the American Mathematical Society. 41 (1): 43–57. doi:10.1090/s0273-0979-03-00993-5. ISSN 0273-0979. Archived (PDF) from the original on 4 March 2016. Retrieved 13 November 2015. The conjecture, which dates back to 1844, was recently proven by the Swiss mathematician Preda Mihăilescu.
219. "Archived copy" (PDF). Archived (PDF) from the original on 2016-10-07. Retrieved 2016-03-18.{{cite web}}: CS1 maint: archived copy as title (link)
220. "Archived copy" (PDF). Archived from the original (PDF) on 2015-09-08. Retrieved 2016-03-18.{{cite web}}: CS1 maint: archived copy as title (link)
221. Bruhn, Henning; Schaudt, Oliver (2001). "Deligne's Conjecture on 1-Motives". arXiv:math/0102150.
222. Breuil, Christophe; Conrad, Brian; Diamond, Fred; Taylor, Richard (2001), "On the modularity of elliptic curves over Q: wild 3-adic exercises", Journal of the American Mathematical Society, 14 (4): 843–939, doi:10.1090/S0894-0347-01-00370-8, ISSN 0894-0347, MR 1839918
223. Luca, Florian (2000). "On a conjecture of Erdős and Stewart" (PDF). Mathematics of Computation. 70 (234): 893–897. Bibcode:2001MaCom..70..893L. doi:10.1090/s0025-5718-00-01178-9. Archived (PDF) from the original on 2016-04-02. Retrieved 2016-03-18.
224. "Archived copy" (PDF). Archived (PDF) from the original on 2016-04-02. Retrieved 2016-03-20.{{cite web}}: CS1 maint: archived copy as title (link)
225. Croot, Ernest S., III (2000), Unit Fractions, Ph.D. thesis, University of Georgia, Athens{{citation}}: CS1 maint: multiple names: authors list (link). Croot, Ernest S., III (2003), "On a coloring conjecture about unit fractions", Annals of Mathematics, 157 (2): 545–556, arXiv:math.NT/0311421, Bibcode:2003math.....11421C, doi:10.4007/annals.2003.157.545, S2CID 13514070{{citation}}: CS1 maint: multiple names: authors list (link)
226. Bruhn, Henning; Schaudt, Oliver (1999). "The Honeycomb Conjecture". arXiv:math/9906042.
227. Bruhn, Henning; Schaudt, Oliver (1999). "Proof of the gradient conjecture of R. Thom". arXiv:math/9906212.
228. Ullmo, E (1998). "Positivité et Discrétion des Points Algébriques des Courbes". Annals of Mathematics. 147 (1): 167–179. arXiv:alg-geom/9606017. doi:10.2307/120987. JSTOR 120987. S2CID 119717506. Zbl 0934.14013.
229. Zhang, S.-W. (1998). "Equidistribution of small points on abelian varieties". Annals of Mathematics. 147 (1): 159–165. doi:10.2307/120986. JSTOR 120986.
230. Lafforgue, Laurent (1998), "Chtoucas de Drinfeld et applications" [Drinfelʹd shtukas and applications], Documenta Mathematica (in French), II: 563–570, ISSN 1431-0635, MR 1648105, archived from the original on 2018-04-27, retrieved 2016-03-18
231. Bruhn, Henning; Schaudt, Oliver (2015). "A formal proof of the Kepler conjecture". arXiv:1501.02155 .
232. Bruhn, Henning; Schaudt, Oliver (1998). "A proof of the dodecahedral conjecture". arXiv:math/9811079.
233. Norio Iwase (1 November 1998). "Ganea's Conjecture on Lusternik-Schnirelmann Category". ResearchGate.
234. Merel, Loïc (1996). ""Bornes pour la torsion des courbes elliptiques sur les corps de nombres" ". Inventiones Mathematicae. 124 (1): 437–449. Bibcode:1996InMat.124..437M. doi:10.1007/s002220050059. MR 1369424. S2CID 3590991.
235. Chen, Zhibo (1996). "Harary's conjectures on integral sum graphs". Discrete Mathematics. 160 (1–3): 241–244. doi:10.1016/0012-365X(95)00163-Q.
236. Wiles, Andrew (1995). "Modular elliptic curves and Fermat's Last Theorem" (PDF). Annals of Mathematics. 141 (3): 443–551. CiteSeerX 10.1.1.169.9076. doi:10.2307/2118559. JSTOR 2118559. OCLC 37032255. Archived (PDF) from the original on 2011-05-10. Retrieved 2016-03-06.
237. Taylor R, Wiles A (1995). "Ring theoretic properties of certain Hecke algebras". Annals of Mathematics. 141 (3): 553–572. CiteSeerX 10.1.1.128.531. doi:10.2307/2118560. JSTOR 2118560. OCLC 37032255.

Further reading

Books discussing problems solved since 1995

• Singh, Simon (2002). Fermat's Last Theorem. Fourth Estate. ISBN 978-1-84115-791-7.
• O'Shea, Donal (2007). The Poincaré Conjecture. Penguin. ISBN 978-1-84614-012-9.
• Szpiro, George G. (2003). Kepler's Conjecture. Wiley. ISBN 978-0-471-08601-7.
• Ronan, Mark (2006). Symmetry and the Monster. Oxford. ISBN 978-0-19-280722-9.

Books discussing unsolved problems

• Chung, Fan; Graham, Ron (1999). Erdös on Graphs: His Legacy of Unsolved Problems. AK Peters. ISBN 978-1-56881-111-6.
• Croft, Hallard T.; Falconer, Kenneth J.; Guy, Richard K. (1994). Unsolved Problems in Geometry. Springer. ISBN 978-0-387-97506-1.
• Guy, Richard K. (2004). Unsolved Problems in Number Theory. Springer. ISBN 978-0-387-20860-2.
• Klee, Victor; Wagon, Stan (1996). Old and New Unsolved Problems in Plane Geometry and Number Theory. The Mathematical Association of America. ISBN 978-0-88385-315-3.
• du Sautoy, Marcus (2003). The Music of the Primes: Searching to Solve the Greatest Mystery in Mathematics. Harper Collins. ISBN 978-0-06-093558-0.
• Derbyshire, John (2003). Prime Obsession: Bernhard Riemann and the Greatest Unsolved Problem in Mathematics. Joseph Henry Press. ISBN 978-0-309-08549-6.
• Devlin, Keith (2006). The Millennium Problems – The Seven Greatest Unsolved* Mathematical Puzzles Of Our Time. Barnes & Noble. ISBN 978-0-7607-8659-8.
• Blondel, Vincent D.; Megrestski, Alexandre (2004). Unsolved problems in mathematical systems and control theory. Princeton University Press. ISBN 978-0-691-11748-5.
• Ji, Lizhen; Poon, Yat-Sun; Yau, Shing-Tung (2013). Open Problems and Surveys of Contemporary Mathematics (volume 6 in the Surveys in Modern Mathematics series) (Surveys of Modern Mathematics). International Press of Boston. ISBN 978-1-57146-278-7.
• Waldschmidt, Michel (2004). "Open Diophantine Problems" (PDF). Moscow Mathematical Journal. 4 (1): 245–305. arXiv:math/0312440. doi:10.17323/1609-4514-2004-4-1-245-305. ISSN 1609-3321. S2CID 11845578. Zbl 1066.11030.
• Mazurov, V. D.; Khukhro, E. I. (1 Jun 2015). "Unsolved Problems in Group Theory. The Kourovka Notebook. No. 18 (English version)". arXiv:1401.0300v6 .
• The Sverdlovsk Notebook is a collection of unsolved problems in semigroup theory.
• Formulation of ${\displaystyle 50}$ unresloved problems for infinite Abelian groups are depicted in the book
• The list of ${\displaystyle 17}$ unresolved problems for Combinatorial Geometry are depicted in the book.
• Several dozens of unresolved problems for Combinatorial Geometry are depicted in the book.
• Many unresolved problems for Graph theory are depicted in the article.
• The list of several unresolved problems converning Maler Conjecture are depicted in the book .

External links

• 24 Unsolved Problems and Rewards for them
• List of links to unsolved problems in mathematics, prizes and research
• Open Problem Garden The collection of open problems in mathematics build on the principle of user editable ("wiki") site
• AIM Problem Lists
• Unsolved Problem of the Week Archive. MathPro Press.
• Ball, John M. "Some Open Problems in Elasticity" (PDF).
• Constantin, Peter. "Some open problems and research directions in the mathematical study of fluid dynamics" (PDF).
• Serre, Denis. "Five Open Problems in Compressible Mathematical Fluid Dynamics" (PDF).
• Unsolved Problems in Number Theory, Logic and Cryptography
• 200 open problems in graph theory
• The Open Problems Project (TOPP), discrete and computational geometry problems
• Kirby's list of unsolved problems in low-dimensional topology
• Erdös' Problems on Graphs
• Unsolved Problems in Virtual Knot Theory and Combinatorial Knot Theory
• Open problems from the 12th International Conference on Fuzzy Set Theory and Its Applications
• List of open problems in inner model theory
• Aizenman, Michael. "Open Problems in Mathematical Physics".
• Barry Simon's 15 Problems in Mathematical Physics

1. The Sverdlovsk Notebook: collects unsolved problems in semigroup theory, Ural State University, 1979
2. The Sverdlovsk Notebook: collects unsolved problems in semigroup theory, Ural State University, 1989
3. Fuks 1974, p. 47, 88, 116, 134, 158, 159, 186, 210, 242, 243, 292, 318. sfn error: no target: CITEREFFuks1974 (help)
4. Boltiansky 1965, p. 83. sfn error: no target: CITEREFBoltiansky1965 (help)
5. Grunbaum 1971, p. 6. sfn error: no target: CITEREFGrunbaum1971 (help)
6. V. G. Vizing Some unresolved problems for Graph theory // Russian Mathematical Surveys, 23:6(144) (1968), 117–134; Russian Math. Surveys, 23:6 (1968), 125–141
7. Sprinjuk 1967, p. 150—154. sfn error: no target: CITEREFSprinjuk1967 (help)

• CS1 maint: DOI inactive as of October 2020
• Unsolved problems in mathematics
• Conjectures
• Lists of unsolved problems
• Mathematics-related lists