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What is the largest graph of positive curvature?
DeVos
;
Mohar
✭
1
Graph Theory
»
Topological G.T.
»
Planar graphs
mdevos
A conjecture on iterated circumcentres
Goddyn
✭✭
1
Geometry
mdevos
Linear-size circuits for stable $0,1 < 2$ sorting?
Regan
✭✭
1
Theoretical Comp. Sci.
»
Complexity
KWRegan
Geodesic cycles and Tutte's Theorem
Georgakopoulos
;
Sprüssel
✭✭
1
Graph Theory
»
Basic G.T.
»
Cycles
Agelos
Divisibility of central binomial coefficients
Graham
✭✭
1
Number Theory
»
Combinatorial N.T.
maxal
A sextic counterexample to Euler's sum of powers conjecture
Euler
✭✭
1
Number Theory
»
Computational N.T.
maxal
Counterexamples to the Baillie-PSW primality test
✭✭
1
Number Theory
»
Computational N.T.
maxal
Coloring and immersion
Abu-Khzam
;
Langston
✭✭✭
1
Graph Theory
»
Coloring
»
Vertex coloring
mdevos
Big Line or Big Clique in Planar Point Sets
Kara
;
Por
;
Wood
✭✭
1
Geometry
David Wood
Matchings extend to Hamiltonian cycles in hypercubes
Ruskey
;
Savage
✭✭
1
Graph Theory
»
Basic G.T.
»
Matchings
Jirka
Seymour's Second Neighbourhood Conjecture
Seymour
✭✭✭
1
Graph Theory
»
Directed Graphs
nkorppi
Snevily's conjecture
Snevily
✭✭✭
1
Number Theory
»
Combinatorial N.T.
mdevos
MacEachen Conjecture
McEachen
✭
1
Number Theory
billymac00
Convex 'Fair' Partitions Of Convex Polygons
Nandakumar
;
Ramana
✭✭
1
Geometry
Nandakumar
End-Devouring Rays
Georgakopoulos
✭
1
Graph Theory
»
Infinite Graphs
Agelos
A discrete iteration related to Pierce expansions
Shallit
✭✭
1
Number Theory
shallit
Simplexity of the n-cube
✭✭✭
1
Geometry
mdevos
Hamiltonicity of Cayley graphs
Rapaport-Strasser
✭✭✭
1
Graph Theory
»
Basic G.T.
»
Cycles
tchow
Odd perfect numbers
Ancient/folklore
✭✭✭
1
Number Theory
azi
Diophantine quintuple conjecture
✭✭
1
Number Theory
maxal
Magic square of squares
LaBar
✭✭
1
Number Theory
»
Computational N.T.
maxal
Frobenius number of four or more integers
✭✭
1
Number Theory
»
Combinatorial N.T.
maxal
Book Thickness of Subdivisions
Blankenship
;
Oporowski
✭✭
1
Graph Theory
David Wood
3-Colourability of Arrangements of Great Circles
Felsner
;
Hurtado
;
Noy
;
Streinu
✭✭
1
Graph Theory
»
Topological G.T.
»
Coloring
David Wood
Exponential Algorithms for Knapsack
Lipton
✭✭
1
Theoretical Comp. Sci.
»
Algorithms
dick lipton
Criterion for boundedness of power series
Rüdinger
✭
1
Analysis
andreasruedinger
Distribution and upper bound of mimic numbers
Bhattacharyya
✭✭
1
Number Theory
»
Analytic N.T.
facility_cttb@i...
Edge-Colouring Geometric Complete Graphs
Hurtado
✭✭
1
Geometry
David Wood
Are there an infinite number of lucky primes?
Lazarus: Gardiner: Metropolis
;
Ulam
✭
1
Number Theory
»
Additive N.T.
cubola zaruka
Sequence defined on multisets
Erickson
✭✭
1
Combinatorics
Martin Erickson
Square achievement game on an n x n grid
Erickson
✭✭
1
Combinatorics
Martin Erickson
Transversal achievement game on a square grid
Erickson
✭✭
1
Combinatorics
Martin Erickson
Strong 5-cycle double cover conjecture
Arthur
;
Hoffmann-Ostenhof
✭✭✭
1
Graph Theory
»
Basic G.T.
»
Cycles
arthur
Star chromatic index of complete graphs
Dvorak
;
Mohar
;
Samal
✭✭
1
Graph Theory
Robert Samal
Point sets with no empty pentagon
Wood
✭
1
Geometry
David Wood
Special Primes
George BALAN
✭
1
Number Theory
maththebalans
Extremal problem on the number of tree endomorphism
Zhicong Lin
✭✭
1
Graph Theory
»
Extremal G.T.
shudeshijie
Vertex Coloring of graph fractional powers
Iradmusa
✭✭✭
1
Graph Theory
Iradmusa
Obstacle number of planar graphs
Alpert
;
Koch
;
Laison
✭
1
Graph Theory
Andrew King
Erdős–Straus conjecture
Erdos
;
Straus
✭✭
1
Number Theory
ACW
Lucas Numbers Modulo m
✭✭
1
Number Theory
Martin Erickson
Length of surreal product
Gonshor
✭
1
Combinatorics
Lukáš Lánský
Minimal graphs with a prescribed number of spanning trees
Azarija
;
Skrekovski
✭✭
1
Graph Theory
azi
Convex uniform 5-polytopes
✭✭
1
Geometry
ACW
Durer's Conjecture
Durer
;
Shephard
✭✭✭
1
Geometry
»
Polytopes
dmoskovich
Mixing Circular Colourings
Brewster
;
Noel
✭
1
Graph Theory
»
Coloring
»
Vertex coloring
Jon Noel
Inequality for square summable complex series
Retkes
✭✭
1
Analysis
tigris35711
Choice Number of k-Chromatic Graphs of Bounded Order
Noel
✭✭
1
Graph Theory
»
Coloring
»
Vertex coloring
Jon Noel
Earth-Moon Problem
Ringel
✭✭
1
Graph Theory
»
Coloring
»
Vertex coloring
fhavet
Bounding the on-line choice number in terms of the choice number
Zhu
✭✭
1
Graph Theory
»
Coloring
»
Vertex coloring
Jon Noel
1
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4
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6
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