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Bounding the on-line choice number in terms of the choice number
Zhu
✭✭
1
Graph Theory
»
Coloring
»
Vertex coloring
Jon Noel
Extremal problem on the number of tree endomorphism
Zhicong Lin
✭✭
1
Graph Theory
»
Extremal G.T.
shudeshijie
Minimum number of arc-disjoint transitive subtournaments of order 3 in a tournament
Yuster
✭✭
0
Graph Theory
fhavet
Woodall's Conjecture
Woodall
✭✭✭
0
Graph Theory
»
Directed Graphs
mdevos
Number of Cliques in Minor-Closed Classes
Wood
✭✭
0
Graph Theory
David Wood
Point sets with no empty pentagon
Wood
✭
1
Geometry
David Wood
Generalised Empty Hexagon Conjecture
Wood
✭✭
1
Geometry
David Wood
Real roots of the flow polynomial
Welsh
✭✭
0
Graph Theory
»
Coloring
»
Nowhere-zero flows
mdevos
Colouring the square of a planar graph
Wegner
✭✭
0
Graph Theory
»
Coloring
»
Vertex coloring
fhavet
Dense rational distance sets in the plane
Ulam
✭✭✭
0
Geometry
mdevos
Triangle-packing vs triangle edge-transversal.
Tuza
✭✭
0
Graph Theory
»
Extremal G.T.
fhavet
5-flow conjecture
Tutte
✭✭✭✭
0
Graph Theory
»
Coloring
»
Nowhere-zero flows
mdevos
4-flow conjecture
Tutte
✭✭✭
0
Graph Theory
»
Coloring
»
Nowhere-zero flows
mdevos
3-flow conjecture
Tutte
✭✭✭
0
Graph Theory
»
Coloring
»
Nowhere-zero flows
mdevos
The Crossing Number of the Complete Bipartite Graph
Turan
✭✭✭
0
Graph Theory
»
Topological G.T.
»
Crossing numbers
Robert Samal
Turán's problem for hypergraphs
Turan
✭✭
0
Graph Theory
»
Hypergraphs
fhavet
Inscribed Square Problem
Toeplitz
✭✭
0
Topology
dlh12
Hamiltonian cycles in line graphs
Thomassen
✭✭✭
0
Graph Theory
»
Basic G.T.
»
Cycles
Robert Samal
Chords of longest cycles
Thomassen
✭✭✭
0
Graph Theory
»
Basic G.T.
»
Cycles
mdevos
Counting 3-colorings of the hex lattice
Thomassen
✭✭
0
Graph Theory
»
Coloring
»
Vertex coloring
mdevos
Arc-disjoint out-branching and in-branching
Thomassen
✭✭
0
Graph Theory
»
Directed Graphs
fhavet
Subgraph of large average degree and large girth.
Thomassen
✭✭
0
Graph Theory
»
Basic G.T.
fhavet
Edge-disjoint Hamilton cycles in highly strongly connected tournaments.
Thomassen
✭✭
0
Graph Theory
»
Directed Graphs
»
Tournaments
fhavet
Partitionning a tournament into k-strongly connected subtournaments.
Thomassen
✭✭
0
Graph Theory
»
Directed Graphs
»
Tournaments
fhavet
Directed path of length twice the minimum outdegree
Thomassé
✭✭✭
0
Graph Theory
»
Directed Graphs
fhavet
Highly connected graphs with no K_n minor
Thomas
✭✭✭
0
Graph Theory
»
Basic G.T.
»
Minors
mdevos
Waring rank of determinant
Teitler
✭✭
0
Algebra
Zach Teitler
Tarski's exponential function problem
Tarski
✭✭
0
Logic
Charles
Coloring the union of degenerate graphs
Tarsi
✭✭
0
Graph Theory
»
Coloring
fhavet
¿Are critical k-forests tight?
Strausz
✭✭
0
Graph Theory
»
Hypergraphs
Dino
Circular flow number of regular class 1 graphs
Steffen
✭✭
0
Graph Theory
»
Coloring
»
Nowhere-zero flows
Eckhard Steffen
Circular flow numbers of $r$-graphs
Steffen
✭✭
0
Graph Theory
Eckhard Steffen
Does the chromatic symmetric function distinguish between trees?
Stanley
✭✭
0
Graph Theory
»
Algebraic G.T.
mdevos
Switching reconstruction conjecture
Stanley
✭✭
0
Graph Theory
fhavet
Snevily's conjecture
Snevily
✭✭✭
1
Number Theory
»
Combinatorial N.T.
mdevos
What is the homotopy type of the group of diffeomorphisms of the 4-sphere?
Smale
✭✭✭✭
0
Topology
rybu
Singmaster's conjecture
Singmaster
✭✭
1
Number Theory
»
Combinatorial N.T.
Zach Teitler
Sidorenko's Conjecture
Sidorenko
✭✭✭
0
Graph Theory
Jon Noel
Edge-Unfolding Convex Polyhedra
Shephard
✭✭
0
Geometry
Erik Demaine
r-regular graphs are not uniquely hamiltonian.
Sheehan
✭✭✭
0
Graph Theory
»
Basic G.T.
»
Cycles
Robert Samal
Unconditional derandomization of Arthur-Merlin games
Shaltiel
;
Umans
✭✭✭
0
Theoretical Comp. Sci.
»
Complexity
»
Derandomization
ormeir
A discrete iteration related to Pierce expansions
Shallit
✭✭
1
Number Theory
shallit
Cycle double cover conjecture
Seymour
;
Szekeres
✭✭✭✭
0
Graph Theory
»
Basic G.T.
»
Cycles
mdevos
Faithful cycle covers
Seymour
✭✭✭
0
Graph Theory
»
Basic G.T.
»
Cycles
mdevos
Seymour's self-minor conjecture
Seymour
✭✭✭
0
Graph Theory
»
Infinite Graphs
mdevos
Seymour's Second Neighbourhood Conjecture
Seymour
✭✭✭
1
Graph Theory
»
Directed Graphs
nkorppi
Seagull problem
Seymour
✭✭✭
0
Graph Theory
»
Basic G.T.
»
Minors
mdevos
Seymour's r-graph conjecture
Seymour
✭✭✭
0
Graph Theory
»
Coloring
»
Edge coloring
mdevos
Order-invariant queries
Segoufin
✭✭
0
Logic
»
Finite Model Theory
dberwanger
Bases of many weights
Schrijver
;
Seymour
✭✭✭
0
Combinatorics
»
Matroid Theory
mdevos
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Recent Activity
Chords of longest cycles
Do any three longest paths in a connected graph have a vertex in common?
Chromatic number of $\frac{3}{3}$-power of graph
3-Edge-Coloring Conjecture
r-regular graphs are not uniquely hamiltonian.
more