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¿Are critical k-forests tight?
Strausz
✭✭
0
Graph Theory
»
Hypergraphs
Dino
Woodall's Conjecture
Woodall
✭✭✭
0
Graph Theory
»
Directed Graphs
mdevos
Wide partition conjecture
Chow
;
Taylor
✭✭
0
Combinatorics
tchow
Which outer reloids are equal to inner ones
Porton
✭✭
0
Topology
porton
Which lattices occur as intervals in subgroup lattices of finite groups?
✭✭✭✭
0
Group Theory
williamdemeo
Which homology 3-spheres bound homology 4-balls?
Ancient/folklore
✭✭✭✭
0
Topology
rybu
Which compact boundaryless 3-manifolds embed smoothly in the 4-sphere?
Kirby
✭✭✭
0
Topology
rybu
What is the smallest number of disjoint spanning trees made a graph Hamiltonian
Goldengorin
✭✭
0
Graph Theory
»
Extremal G.T.
boris
What is the largest graph of positive curvature?
DeVos
;
Mohar
✭
1
Graph Theory
»
Topological G.T.
»
Planar graphs
mdevos
What is the homotopy type of the group of diffeomorphisms of the 4-sphere?
Smale
✭✭✭✭
0
Topology
rybu
What are hyperfuncoids isomorphic to?
Porton
✭✭
0
Topology
porton
Weighted colouring of hexagonal graphs.
McDiarmid
;
Reed
✭✭
0
Graph Theory
»
Coloring
»
Vertex coloring
fhavet
Weak saturation of the cube in the clique
Morrison
;
Noel
✭
1
Graph Theory
»
Extremal G.T.
Jon Noel
Weak pentagon problem
Samal
✭✭
0
Graph Theory
»
Coloring
»
Homomorphisms
Robert Samal
Waring rank of determinant
Teitler
✭✭
0
Algebra
Zach Teitler
Wall-Sun-Sun primes and Fibonacci divisibility
✭✭
0
Number Theory
»
Computational N.T.
adudzik
Vertex Cover Integrality Gap
Atserias
✭✭
0
Logic
»
Finite Model Theory
dberwanger
Vertex Coloring of graph fractional powers
Iradmusa
✭✭✭
1
Graph Theory
Iradmusa
Upgrading a completary multifuncoid
Porton
✭✭
0
Topology
porton
Unsolvability of word problem for 2-knot complements
Gordon
✭✭✭
0
Topology
rybu
Universal Steiner triple systems
Grannell
;
Griggs
;
Knor
;
Skoviera
✭✭
0
Graph Theory
»
Coloring
»
Edge coloring
macajova
Universal point sets for planar graphs
Mohar
✭✭✭
0
Graph Theory
»
Topological G.T.
»
Drawings
mdevos
Universal highly arc transitive digraphs
Cameron
;
Praeger
;
Wormald
✭✭✭
0
Graph Theory
»
Infinite Graphs
mdevos
Unit vector flows
Jain
✭✭
0
Graph Theory
»
Coloring
»
Nowhere-zero flows
mdevos
Unions of triangle free graphs
Erdos
;
Hajnal
✭✭✭
0
Graph Theory
»
Infinite Graphs
mdevos
Unfriendly partitions
Cowan
;
Emerson
✭✭✭
0
Graph Theory
»
Infinite Graphs
mdevos
Unconditional derandomization of Arthur-Merlin games
Shaltiel
;
Umans
✭✭✭
0
Theoretical Comp. Sci.
»
Complexity
»
Derandomization
ormeir
Twin prime conjecture
✭✭✭✭
0
Number Theory
kaushiks.nitt
Turán's problem for hypergraphs
Turan
✭✭
0
Graph Theory
»
Hypergraphs
fhavet
Turán Problem for $10$-Cycles in the Hypercube
Erdos
✭✭
0
Combinatorics
Jon Noel
Turán number of a finite family.
Erdos
;
Simonovits
✭✭
0
Graph Theory
fhavet
Triangle-packing vs triangle edge-transversal.
Tuza
✭✭
0
Graph Theory
»
Extremal G.T.
fhavet
Triangle free strongly regular graphs
✭✭✭
0
Graph Theory
»
Algebraic G.T.
mdevos
Transversal achievement game on a square grid
Erickson
✭✭
1
Combinatorics
Martin Erickson
trace inequality
✭✭
0
Algebra
Miwa Lin
Total Colouring Conjecture
Behzad
✭✭✭
0
Graph Theory
»
Coloring
Iradmusa
Three-chromatic (0,2)-graphs
Payan
✭✭
0
Graph Theory
»
Coloring
Gordon Royle
The Two Color Conjecture
Neumann-Lara
✭✭
0
Graph Theory
»
Directed Graphs
mdevos
The three 4-flows conjecture
DeVos
✭✭
0
Graph Theory
»
Coloring
»
Nowhere-zero flows
mdevos
The stubborn list partition problem
Cameron
;
Eschen
;
Hoang
;
Sritharan
✭✭
0
Graph Theory
»
Graph Algorithms
mdevos
The robustness of the tensor product
Ben-Sasson
;
Sudan
✭✭✭
0
Theoretical Comp. Sci.
»
Coding Theory
ormeir
The Riemann Hypothesis
Riemann
✭✭✭✭
0
Number Theory
»
Analytic N.T.
eric
The permanent conjecture
Kahn
✭✭
0
Combinatorics
»
Matrices
mdevos
The large sets conjecture
Brown
;
Graham
;
Landman
✭✭✭
0
Combinatorics
»
Ramsey Theory
vjungic
The intersection of two perfect matchings
Macajova
;
Skoviera
✭✭
0
Graph Theory
»
Basic G.T.
»
Matchings
mdevos
The Hodge Conjecture
Hodge
✭✭✭✭
0
Geometry
»
Algebraic Geometry
Charles
The Erdos-Turan conjecture on additive bases
Erdos
;
Turan
✭✭✭✭
0
Number Theory
»
Additive N.T.
mdevos
The Erdös-Hajnal Conjecture
Erdos
;
Hajnal
✭✭✭
0
Graph Theory
»
Extremal G.T.
mdevos
The Double Cap Conjecture
Kalai
✭✭
0
Combinatorics
Jon Noel
The Crossing Number of the Hypercube
Erdos
;
Guy
✭✭
0
Graph Theory
»
Topological G.T.
»
Crossing numbers
Robert Samal
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