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Giuga's Conjecture on Primality
Giuseppe Giuga
✭✭
0
Number Theory
princeps
Alexa's Conjecture on Primality
Alexa
✭✭
0
Number Theory
princeps
Combinatorial covering designs
Gordon
;
Mills
;
Rödl
;
Schönheim
✭
0
Combinatorics
»
Designs
Pseudonym
Cores of Cayley graphs
Samal
✭✭
0
Graph Theory
»
Coloring
»
Homomorphisms
Robert Samal
Pentagon problem
Nesetril
✭✭✭
0
Graph Theory
»
Coloring
»
Homomorphisms
Robert Samal
The Crossing Number of the Complete Graph
✭✭✭
0
Graph Theory
»
Topological G.T.
»
Crossing numbers
Robert Samal
The Crossing Number of the Complete Bipartite Graph
Turan
✭✭✭
0
Graph Theory
»
Topological G.T.
»
Crossing numbers
Robert Samal
The Crossing Number of the Hypercube
Erdos
;
Guy
✭✭
0
Graph Theory
»
Topological G.T.
»
Crossing numbers
Robert Samal
Barnette's Conjecture
Barnette
✭✭✭
0
Graph Theory
»
Basic G.T.
»
Cycles
Robert Samal
List colorings of edge-critical graphs
Mohar
✭✭
0
Graph Theory
»
Coloring
»
Edge coloring
Robert Samal
Laplacian Degrees of a Graph
Guo
✭✭
0
Graph Theory
»
Algebraic G.T.
Robert Samal
Weak pentagon problem
Samal
✭✭
0
Graph Theory
»
Coloring
»
Homomorphisms
Robert Samal
r-regular graphs are not uniquely hamiltonian.
Sheehan
✭✭✭
0
Graph Theory
»
Basic G.T.
»
Cycles
Robert Samal
Infinite uniquely hamiltonian graphs
Mohar
✭✭
0
Graph Theory
»
Infinite Graphs
Robert Samal
Hamiltonian cycles in line graphs
Thomassen
✭✭✭
0
Graph Theory
»
Basic G.T.
»
Cycles
Robert Samal
Hamiltonian cycles in line graphs of infinite graphs
Georgakopoulos
✭✭
0
Graph Theory
»
Infinite Graphs
Robert Samal
Hamiltonian cycles in powers of infinite graphs
Georgakopoulos
✭✭
0
Graph Theory
»
Infinite Graphs
Robert Samal
Odd incongruent covering systems
Erdos
;
Selfridge
✭✭✭
0
Number Theory
»
Combinatorial N.T.
Robert Samal
Covering systems with big moduli
Erdos
;
Selfridge
✭✭
0
Number Theory
»
Combinatorial N.T.
Robert Samal
Oriented chromatic number of planar graphs
✭✭
0
Graph Theory
»
Coloring
»
Vertex coloring
Robert Samal
Crossing sequences
Archdeacon
;
Bonnington
;
Siran
✭✭
0
Graph Theory
»
Topological G.T.
»
Crossing numbers
Robert Samal
Star chromatic index of cubic graphs
Dvorak
;
Mohar
;
Samal
✭✭
0
Graph Theory
Robert Samal
Star chromatic index of complete graphs
Dvorak
;
Mohar
;
Samal
✭✭
1
Graph Theory
Robert Samal
Circular choosability of planar graphs
Mohar
✭
0
Graph Theory
»
Coloring
»
Homomorphisms
rosskang
Elementary symmetric of a sum of matrices
✭✭✭
0
Algebra
rscosa
Smooth 4-dimensional Schoenflies problem
Alexander
✭✭✭✭
0
Topology
rybu
Smooth 4-dimensional Poincare conjecture
Poincare
;
Smale
;
Stallings
✭✭✭✭
0
Topology
rybu
Slice-ribbon problem
Fox
✭✭✭✭
0
Topology
rybu
Realisation problem for the space of knots in the 3-sphere
Budney
✭✭
0
Topology
rybu
Which homology 3-spheres bound homology 4-balls?
Ancient/folklore
✭✭✭✭
0
Topology
rybu
Fundamental group torsion for subsets of Euclidean 3-space
Ancient/folklore
✭✭
0
Topology
rybu
Which compact boundaryless 3-manifolds embed smoothly in the 4-sphere?
Kirby
✭✭✭
0
Topology
rybu
What is the homotopy type of the group of diffeomorphisms of the 4-sphere?
Smale
✭✭✭✭
0
Topology
rybu
Is there an algorithm to determine if a triangulated 4-manifold is combinatorially equivalent to the 4-sphere?
Novikov
✭✭✭
0
Topology
rybu
Unsolvability of word problem for 2-knot complements
Gordon
✭✭✭
0
Topology
rybu
The 4x5 chessboard complex is the complement of a link, which link?
David Eppstein
✭✭
0
Topology
rybu
Graphs of exact colorings
✭✭
0
Algebra
sabisood
Imbalance conjecture
Kozerenko
✭✭
0
Graph Theory
Sergiy Kozerenko
A discrete iteration related to Pierce expansions
Shallit
✭✭
1
Number Theory
shallit
Extremal problem on the number of tree endomorphism
Zhicong Lin
✭✭
1
Graph Theory
»
Extremal G.T.
shudeshijie
Roller Coaster permutations
Ahmed
;
Snevily
✭✭✭
0
Combinatorics
Tanbir Ahmed
Linear Hypergraphs with Dimension 3
Ossona de Mendez
;
Rosenstiehl
;
de Fraysseix
✭✭
0
Graph Theory
»
Topological G.T.
»
Drawings
taxipom
Wide partition conjecture
Chow
;
Taylor
✭✭
0
Combinatorics
tchow
Kneser–Poulsen conjecture
Kneser
;
Poulsen
✭✭✭
0
Geometry
tchow
Hamiltonicity of Cayley graphs
Rapaport-Strasser
✭✭✭
1
Graph Theory
»
Basic G.T.
»
Cycles
tchow
Frankl's union-closed sets conjecture
Frankl
✭✭
0
Graph Theory
»
Hypergraphs
tchow
Edge list coloring conjecture
✭✭✭
0
Graph Theory
»
Coloring
»
Edge coloring
tchow
Inverse Galois Problem
Hilbert
✭✭✭✭
0
Group Theory
tchow
Invariant subspace problem
✭✭✭
0
Analysis
tchow
Shannon capacity of the seven-cycle
✭✭✭
0
Graph Theory
tchow
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