We answer two open questions posed by Cameron and Nesetril concerning homomorphismhomogeneous graphs. In particular we show, by giving a characterization of these graphs, that ext...
: We prove that the strong product G1 G2 of G1 and G2 is Z3-flow contractible if and only if G1 G2 is not T K2, where T is a tree (we call T K2 a K4-tree). It follows that G1 G2 ad...
Wilfried Imrich, Iztok Peterin, Simon Spacapan, Cu...
An edge-colored graph G is rainbow edge-connected if any two vertices are connected by a path whose edges have distinct colors. The rainbow connection of a connected graph G, deno...
The crossing number, cr(G), of a graph G is the least number of crossing points in any drawing of G in the plane. According to the Crossing Lemma of Ajtai, Chv´atal, Newborn, Sze...
Let G(V, E) be a simple, undirected graph where V is the set of vertices and E is the set of edges. A b-dimensional cube is a Cartesian product I1 × I2 × · · · × Ib, where ea...