Equitable coloring planar graphs with large girth Original Research Article

A proper vertex coloring of a graph G is equitable if the size of color classes differ by at most one. The equitable chromatic threshold of G, denoted by image, is the smallest integer m such that G is equitably n-colorable for all image. We prove that image if G is a non-bipartite planar graph with girth image and image or G is a 2-connected outerplanar graph with girth image.