Transactions on Combinatorics (Jun 2016)
On the number of connected components of divisibility graph for certain simple groups
Abstract
The divisibility graph D(G) D(G) for a finite group G G is a graph with vertex set cs(G)∖{1} cs(G)∖{1} where cs(G) cs(G) is the set of conjugacy class sizes of G G. Two vertices a a and b b are adjacent whenever a a divides b b or b b divides a a. In this paper we will find the number of connected components of D(G) D(G) where G G is a simple Zassenhaus group or an sporadic simple group.