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We prove a theorem guaranteeing special paths of faces in 2-connected plane graphs. As a corollary, we obtain a new proof of Thomassen’s theorem that every 4-connected planar graph is Hamiltonian-connected.

A new spectral method for determining the number of spanning trees.

Cvetkovic, D.M., Gutman, I. (1981)

Publications de l'Institut Mathématique. Nouvelle Série

A new sphere packing in 20 dimensions.

Alexander Vardy (1995)

Inventiones mathematicae

A new statistic on linear and circular $r$ -mino arrangements.

Shattuck, Mark A., Wagner, Carl G. (2006)

The Electronic Journal of Combinatorics [electronic only]

A new triple sum combinatorial identity.

Sinyor, Joseph, Tefera, Akalu (2002)

International Journal of Mathematics and Mathematical Sciences

A new upper bound for the chromatic number of a graph

Ingo Schiermeyer (2007)

Discussiones Mathematicae Graph Theory

Let G be a graph of order n with clique number ω(G), chromatic number χ(G) and independence number α(G). We show that χ(G) ≤ [(n+ω+1-α)/2]. Moreover, χ(G) ≤ [(n+ω-α)/2], if either ω + α = n + 1 and G is not a split graph or α + ω = n - 1 and G contains no induced $K_{ω + 3} - C ₅$ .

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A new method to construct lower bounds for van der Waerden numbers.

A New Necessary Condition for the Vertex Visibility Graphs of Simple Polygons.

A new proof of a characterization of the set of all geodesics in a connected graph

A new proof of a theorem of Dirac on the number of edges in critical graphs.

A new proof of some identities of Bressoud.

A new proof of the four-colour theorem.

A new proof of the $q$ -Dixon identity

A New Proof of the Szeged-Wiener Theorem

A New Proof that 4-Connected Planar Graphs are Hamiltonian-Connected

A new spectral method for determining the number of spanning trees.

A new sphere packing in 20 dimensions.

A new statistic on linear and circular $r$ -mino arrangements.

A new triple sum combinatorial identity.

A new upper bound for the chromatic number of a graph

A new upper bound for the Laplacian spectral radius of a graph.

A new upper bound on the total domination number of a graph.

A `nice' bijection for a content formula for skew semistandard Young tableaux.

A non graph theory approach to Ulam's conjecture

A non-differentiablity result for the inversion operator between Sobolev spaces.

A Nonuniform Matroid Which Violates the Isotopy Conjecture.

Currently displaying 401 – 420 of 8549