On the regular power graph on the conjugacy classes of finite groups

Th e (undirected) power graph on the conjugacy classes PC (G) of a group G is a simple graph in which the vertices are the conjugacy classes of G and two distinct vertices C and C′ are adjacent in PC (G) if one is a subset of a power of the other. In this paper, we describe groups whose associated graphs are k-regular for k = 5; 6.