Open Problems


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Ramsey properties of Cayley graphsAlon✭✭✭0Graph Theory » Algebraic G.T.mdevos
Splitting a digraph with minimum outdegree constraintsAlon✭✭✭0Graph Theory » Directed Graphsfhavet
List chromatic number and maximum degree of bipartite graphsAlon✭✭0Graph Theory » Coloring » Vertex coloringfhavet
List Colourings of Complete Multipartite Graphs with 2 Big PartsAllagan✭✭1Graph Theory » Coloring » Vertex coloringJon Noel
Smooth 4-dimensional Schoenflies problemAlexander✭✭✭✭0Topologyrybu
Alexa's Conjecture on PrimalityAlexa✭✭0Number Theoryprinceps
Partial List ColoringAlbertson; Grossman; Haas✭✭✭0Graph Theory » Coloring » Vertex coloringIradmusa
Crossing numbers and coloringAlbertson✭✭✭0Graph Theory » Topological G.T. » Crossing numbersmdevos
PTAS for feedback arc set in tournamentsAilon; Alon✭✭0Graph Theory » Graph Algorithmsfhavet
Roller Coaster permutationsAhmed; Snevily✭✭✭0CombinatoricsTanbir Ahmed
Aharoni-Berger conjectureAharoni; Berger✭✭✭0Combinatorics » Matroid Theorymdevos
Strong colorabilityAharoni; Alon; Haxell✭✭✭0Graph Theory » Coloring » Vertex coloringberger
Strong matchings and coversAharoni✭✭✭0Graph Theory » Infinite Graphsmdevos
Growth of finitely presented groupsAdyan✭✭✭0Group Theorymdevos
Antidirected trees in digraphsAddario-Berry; Havet; Linhares Sales; Reed; Thomassé✭✭0Graph Theory » Directed Graphsfhavet
Ádám's ConjectureÁdám✭✭✭0Graph Theory » Directed Graphsfhavet
Coloring and immersionAbu-Khzam; Langston✭✭✭1Graph Theory » Coloring » Vertex coloringmdevos
Large induced forest in a planar graph.Abertson; Berman✭✭0Graph Theory » Topological G.T.fhavet
Decomposing eulerian graphs✭✭✭0Graph Theory » Basic G.T. » Cyclesmdevos
Subset-sums equality (pigeonhole version)✭✭✭0Theoretical Comp. Sci. » Complexitymdevos
Consecutive non-orientable embedding obstructions✭✭✭0Graph Theory » Topological G.T. » GenusBruce Richter
The Crossing Number of the Complete Graph✭✭✭0Graph Theory » Topological G.T. » Crossing numbersRobert Samal
Triangle free strongly regular graphs✭✭✭0Graph Theory » Algebraic G.T.mdevos
Graceful Tree Conjecture✭✭✭0Graph Theory » Coloring » Labelingkintali
Oriented chromatic number of planar graphs✭✭0Graph Theory » Coloring » Vertex coloringRobert Samal
Counterexamples to the Baillie-PSW primality test✭✭1Number Theory » Computational N.T.maxal
Davenport's constant✭✭✭0Number Theory » Combinatorial N.T.mdevos
Wall-Sun-Sun primes and Fibonacci divisibility✭✭0Number Theory » Computational N.T.adudzik
Algebraic independence of pi and e✭✭✭0Number Theoryporton
Simplexity of the n-cube✭✭✭1Geometrymdevos
Edge list coloring conjecture✭✭✭0Graph Theory » Coloring » Edge coloringtchow
Discrete Logarithm Problem✭✭✭0Theoretical Comp. Sci. » Complexitycplxphil
Monochromatic empty triangles✭✭✭0Geometrymdevos
trace inequality✭✭0AlgebraMiwa Lin
Diophantine quintuple conjecture✭✭1Number Theorymaxal
Frobenius number of four or more integers✭✭1Number Theory » Combinatorial N.T.maxal
Elementary symmetric of a sum of matrices✭✭✭0Algebrarscosa
Invariant subspace problem✭✭✭0Analysistchow
Shannon capacity of the seven-cycle✭✭✭0Graph Theorytchow
Inequality of the means✭✭✭0Geometrymdevos
Twin prime conjecture✭✭✭✭0Number Theorykaushiks.nitt
Partition of Complete Geometric Graph into Plane Trees✭✭0GeometryDavid Wood
Odd cycles and low oddness✭✭0Graph TheoryGagik
Perfect 2-error-correcting codes over arbitrary finite alphabets.✭✭0Combinatorics » Codesdavidcullen
Perfect cuboid✭✭0Number Theory » Computational N.T.tsihonglau
Finite Lattice Representation Problem✭✭✭✭0Algebrawilliamdemeo
Sticky Cantor sets✭✭0Topologyporton
Nonseparating planar continuum✭✭0Topologyporton
Which lattices occur as intervals in subgroup lattices of finite groups?✭✭✭✭0Group Theorywilliamdemeo
Primitive pythagorean n-tuple tree✭✭0Number Theorytsihonglau
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