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Odd-cycle transversal in triangle-free graphs
Erdos
;
Faudree
;
Pach
;
Spencer
✭✭
0
Graph Theory
»
Extremal G.T.
fhavet
Odd perfect numbers
Ancient/folklore
✭✭✭
1
Number Theory
azi
Odd incongruent covering systems
Erdos
;
Selfridge
✭✭✭
0
Number Theory
»
Combinatorial N.T.
Robert Samal
Odd cycles and low oddness
✭✭
0
Graph Theory
Gagik
Obstacle number of planar graphs
Alpert
;
Koch
;
Laison
✭
1
Graph Theory
Andrew King
Number of Cliques in Minor-Closed Classes
Wood
✭✭
0
Graph Theory
David Wood
Nonseparating planar continuum
✭✭
0
Topology
porton
Non-edges vs. feedback edge sets in digraphs
Chudnovsky
;
Seymour
;
Sullivan
✭✭✭
0
Graph Theory
»
Directed Graphs
mdevos
Negative association in uniform forests
Pemantle
✭✭
0
Graph Theory
»
Probabilistic G.T.
mdevos
Nearly spanning regular subgraphs
Alon
;
Mubayi
✭✭✭
0
Graph Theory
»
Basic G.T.
mdevos
Multicolour Erdős--Hajnal Conjecture
Erdos
;
Hajnal
✭✭✭
0
Graph Theory
»
Extremal G.T.
Jon Noel
MSO alternation hierarchy over pictures
Grandjean
✭✭
0
Logic
»
Finite Model Theory
dberwanger
Monotone 4-term Arithmetic Progressions
Davis
;
Entringer
;
Graham
;
Simmons
✭✭
0
Combinatorics
vjungic
Monochromatic vertex colorings inherited from Perfect Matchings
✭✭✭
1
Graph Theory
Mario Krenn
Monochromatic reachability or rainbow triangles
Sands
;
Sauer
;
Woodrow
✭✭✭
0
Graph Theory
»
Directed Graphs
»
Tournaments
mdevos
Monochromatic reachability in arc-colored digraphs
Sands
;
Sauer
;
Woodrow
✭✭✭
0
Graph Theory
»
Directed Graphs
fhavet
Monochromatic empty triangles
✭✭✭
0
Geometry
mdevos
Monadic second-order logic with cardinality predicates
Courcelle
✭✭
0
Logic
»
Finite Model Theory
dberwanger
Mixing Circular Colourings
Brewster
;
Noel
✭
1
Graph Theory
»
Coloring
»
Vertex coloring
Jon Noel
Minimum number of arc-disjoint transitive subtournaments of order 3 in a tournament
Yuster
✭✭
0
Graph Theory
fhavet
Minimal graphs with a prescribed number of spanning trees
Azarija
;
Skrekovski
✭✭
1
Graph Theory
azi
Melnikov's valency-variety problem
Melnikov
✭
0
Graph Theory
»
Coloring
»
Vertex coloring
asp
Matchings extend to Hamiltonian cycles in hypercubes
Ruskey
;
Savage
✭✭
1
Graph Theory
»
Basic G.T.
»
Matchings
Jirka
Matching cut and girth
✭✭
0
Graph Theory
w
Mapping planar graphs to odd cycles
Jaeger
✭✭✭
0
Graph Theory
»
Coloring
»
Homomorphisms
mdevos
Magic square of squares
LaBar
✭✭
1
Number Theory
»
Computational N.T.
maxal
MacEachen Conjecture
McEachen
✭
1
Number Theory
billymac00
Lucas Numbers Modulo m
✭✭
1
Number Theory
Martin Erickson
Lovász Path Removal Conjecture
Lovasz
✭✭
0
Graph Theory
fhavet
Long rainbow arithmetic progressions
Fox
;
Jungic
;
Mahdian
;
Nesetril
;
Radoicic
✭✭
0
Combinatorics
vjungic
Long directed cycles in diregular digraphs
Jackson
✭✭✭
0
Graph Theory
»
Directed Graphs
fhavet
Lonely runner conjecture
Cusick
;
Wills
✭✭✭
0
Number Theory
mdevos
List Total Colouring Conjecture
Borodin
;
Kostochka
;
Woodall
✭✭
0
Graph Theory
»
Coloring
Jon Noel
List Hadwiger Conjecture
Kawarabayashi
;
Mohar
✭✭
0
Graph Theory
»
Coloring
»
Vertex coloring
David Wood
List Colourings of Complete Multipartite Graphs with 2 Big Parts
Allagan
✭✭
1
Graph Theory
»
Coloring
»
Vertex coloring
Jon Noel
List colorings of edge-critical graphs
Mohar
✭✭
0
Graph Theory
»
Coloring
»
Edge coloring
Robert Samal
List chromatic number and maximum degree of bipartite graphs
Alon
✭✭
0
Graph Theory
»
Coloring
»
Vertex coloring
fhavet
Linial-Berge path partition duality
Berge
;
Linial
✭✭✭
0
Graph Theory
»
Coloring
berger
Linear-size circuits for stable $0,1 < 2$ sorting?
Regan
✭✭
1
Theoretical Comp. Sci.
»
Complexity
KWRegan
Linear Hypergraphs with Dimension 3
Ossona de Mendez
;
Rosenstiehl
;
de Fraysseix
✭✭
0
Graph Theory
»
Topological G.T.
»
Drawings
taxipom
Lindelöf hypothesis
Lindelöf
✭✭
0
Number Theory
»
Analytic N.T.
porton
Length of surreal product
Gonshor
✭
1
Combinatorics
Lukáš Lánský
Large induced forest in a planar graph.
Abertson
;
Berman
✭✭
0
Graph Theory
»
Topological G.T.
fhavet
Large acyclic induced subdigraph in a planar oriented graph.
Harutyunyan
✭✭
0
Graph Theory
»
Directed Graphs
fhavet
Laplacian Degrees of a Graph
Guo
✭✭
0
Graph Theory
»
Algebraic G.T.
Robert Samal
Kriesell's Conjecture
Kriesell
✭✭
0
Graph Theory
»
Basic G.T.
»
Connectivity
Jon Noel
KPZ Universality Conjecture
✭✭✭
0
Probability
Tomas Kojar
Kneser–Poulsen conjecture
Kneser
;
Poulsen
✭✭✭
0
Geometry
tchow
Jorgensen's Conjecture
Jorgensen
✭✭✭
0
Graph Theory
»
Basic G.T.
»
Minors
mdevos
Jones' conjecture
Kloks
;
Lee
;
Liu
✭✭
0
Graph Theory
»
Basic G.T.
»
Cycles
cmlee
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