We prove that the out-distance sequence {f+ (k)} of a vertex-transitive digraph of finite or infinite degree satisfies f+ (k + 1) f+ (k)2 for k 1, where f+ (k) denotes the numbe...
In this paper we show that, if G is a Berge graph such that neither G nor its complement G contains certain induced subgraphs, named proper wheels and long prisms, then either G i...
We introduce and discuss generalizations of the problem of independent transversals. Given a graph property R, we investigate whether any graph of maximum degree at most d with a ...
Given a universal binary countable homogeneous structure U and n , there is a partition of the induced n-element substructures of U into finitely many classes so that for any par...