摘要
The notion of the star chromatic number of a graph is a generalization of the chromatic number. In this paper. we calculate the star chromatic numbers of three infinite families of planar graphs. The first two families are derived from a 3-or 5-wheel by subdivisions. their star chromatic numbers being 2+2/(2n + 1). 2+3/(3n + 1)and 2+3/ (3n - 1), respectively. The third family of planar graphs are derived from n odd wheels by Hajos construction with star chromatic numbers 3 + 1/n. which is a generalization of one resnlt of Gao et al.
The notion of the star chromatic number of a graph is a generalization of the chromatic number. In this paper. we calculate the star chromatic numbers of three infinite families of planar graphs. The first two families are derived from a 3-or 5-wheel by subdivisions. their star chromatic numbers being 2+2/(2n + 1). 2+3/(3n + 1)and 2+3/ (3n - 1), respectively. The third family of planar graphs are derived from n odd wheels by Hajos construction with star chromatic numbers 3 + 1/n. which is a generalization of one resnlt of Gao et al.
基金
Supported by Project 1012003