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The 3n+1 conjecture
Collatz
✭✭✭
0
Number Theory
»
Combinatorial N.T.
dododododo
Durer's Conjecture
Durer
;
Shephard
✭✭✭
1
Geometry
»
Polytopes
dmoskovich
Subgroup formed by elements of order dividing n
Frobenius
✭✭
0
Group Theory
dlh12
Inscribed Square Problem
Toeplitz
✭✭
0
Topology
dlh12
Burnside problem
Burnside
✭✭✭✭
0
Group Theory
dlh12
¿Are critical k-forests tight?
Strausz
✭✭
0
Graph Theory
»
Hypergraphs
Dino
Exponential Algorithms for Knapsack
Lipton
✭✭
1
Theoretical Comp. Sci.
»
Algorithms
dick lipton
Double-critical graph conjecture
Erdos
;
Lovasz
✭✭
0
Graph Theory
»
Coloring
»
Vertex coloring
DFR
Average diameter of a bounded cell of a simple arrangement
Deza
;
Terlaky
;
Zinchenko
✭✭
0
Geometry
deza
Continous analogue of Hirsch conjecture
Deza
;
Terlaky
;
Zinchenko
✭✭
0
Geometry
»
Polytopes
deza
Fixed-point logic with counting
Blass
✭✭
0
Logic
»
Finite Model Theory
dberwanger
Order-invariant queries
Segoufin
✭✭
0
Logic
»
Finite Model Theory
dberwanger
Monadic second-order logic with cardinality predicates
Courcelle
✭✭
0
Logic
»
Finite Model Theory
dberwanger
Blatter-Specker Theorem for ternary relations
Makowsky
✭✭
0
Logic
»
Finite Model Theory
dberwanger
MSO alternation hierarchy over pictures
Grandjean
✭✭
0
Logic
»
Finite Model Theory
dberwanger
Vertex Cover Integrality Gap
Atserias
✭✭
0
Logic
»
Finite Model Theory
dberwanger
Dividing up the unrestricted partitions
David S.
;
Newman
✭✭
0
Combinatorics
DavidSNewman
Perfect 2-error-correcting codes over arbitrary finite alphabets.
✭✭
0
Combinatorics
»
Codes
davidcullen
Big Line or Big Clique in Planar Point Sets
Kara
;
Por
;
Wood
✭✭
1
Geometry
David Wood
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
Number of Cliques in Minor-Closed Classes
Wood
✭✭
0
Graph Theory
David Wood
Edge-Colouring Geometric Complete Graphs
Hurtado
✭✭
1
Geometry
David Wood
Partition of Complete Geometric Graph into Plane Trees
✭✭
0
Geometry
David Wood
Point sets with no empty pentagon
Wood
✭
1
Geometry
David Wood
Forcing a $K_6$-minor
Barát
;
Joret
;
Wood
✭✭
0
Graph Theory
»
Basic G.T.
»
Minors
David Wood
Dirac's Conjecture
Dirac
✭✭
0
Geometry
David Wood
Fractional Hadwiger
Harvey
;
Reed
;
Seymour
;
Wood
✭✭
1
Graph Theory
David Wood
Forcing a 2-regular minor
Reed
;
Wood
✭✭
1
Graph Theory
»
Basic G.T.
»
Minors
David Wood
General position subsets
Gowers
✭✭
0
Geometry
David Wood
Generalised Empty Hexagon Conjecture
Wood
✭✭
1
Geometry
David Wood
List Hadwiger Conjecture
Kawarabayashi
;
Mohar
✭✭
0
Graph Theory
»
Coloring
»
Vertex coloring
David Wood
Chromatic Number of Common Graphs
Hatami
;
Hladký
;
Kráľ
;
Norine
;
Razborov
✭✭
0
Graph Theory
David Wood
Chromatic number of associahedron
Fabila-Monroy
;
Flores-Penaloza
;
Huemer
;
Hurtado
;
Urrutia
;
Wood
✭✭
1
Geometry
David Wood
Refuting random 3SAT-instances on $O(n)$ clauses (weak form)
Feige
✭✭✭
0
Theoretical Comp. Sci.
»
Complexity
»
Hardness of Approximation
cwenner
Sums of independent random variables with unbounded variance
Feige
✭✭
0
Theoretical Comp. Sci.
cwenner
P vs. PSPACE
Folklore
✭✭✭
0
Theoretical Comp. Sci.
»
Complexity
cwenner
Are there an infinite number of lucky primes?
Lazarus: Gardiner: Metropolis
;
Ulam
✭
1
Number Theory
»
Additive N.T.
cubola zaruka
Discrete Logarithm Problem
✭✭✭
0
Theoretical Comp. Sci.
»
Complexity
cplxphil
Jones' conjecture
Kloks
;
Lee
;
Liu
✭✭
0
Graph Theory
»
Basic G.T.
»
Cycles
cmlee
Are different notions of the crossing number the same?
Pach
;
Tóth
✭✭✭
0
Graph Theory
»
Topological G.T.
»
Crossing numbers
cibulka
P vs. BPP
Folklore
✭✭✭
0
Theoretical Comp. Sci.
»
Complexity
»
Derandomization
Charles R Great...
Jacobian Conjecture
Keller
✭✭✭
0
Geometry
»
Algebraic Geometry
Charles
Schanuel's Conjecture
Schanuel
✭✭✭✭
0
Number Theory
»
Analytic N.T.
Charles
Tarski's exponential function problem
Tarski
✭✭
0
Logic
Charles
The Hodge Conjecture
Hodge
✭✭✭✭
0
Geometry
»
Algebraic Geometry
Charles
Consecutive non-orientable embedding obstructions
✭✭✭
0
Graph Theory
»
Topological G.T.
»
Genus
Bruce Richter
Concavity of van der Waerden numbers
Landman
✭✭
0
Combinatorics
»
Ramsey Theory
Bruce Landman
What is the smallest number of disjoint spanning trees made a graph Hamiltonian
Goldengorin
✭✭
0
Graph Theory
»
Extremal G.T.
boris
MacEachen Conjecture
McEachen
✭
1
Number Theory
billymac00
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Chords of longest cycles
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3-Edge-Coloring Conjecture
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