Graph colouring remains a central topic in graph theory, providing the mathematical framework for assigning colours to the elements of a graph under specific constraints. In particular, the colouring ...

Two computer scientists found — in the unlikeliest of places — just the idea they needed to make a big leap in graph theory. This past October, as Jacob Holm and Eva Rotenberg were thumbing through a ...

Abstract: In this paper, Heawood's counterexample graph is artificially colored by using the algorithm of planar graph four-colorable based on path homotopy search, which verifies the feasibility and ...

Abstract: A graph consists of a set of vertices and a set of edges, each joining two vertices. A graph is planar if it can be embedded in the plane so that no two edges intersect geometrically except ...