et G be a finite group. Let l(G) be the number of conjugacy |?(G)| if and only if G?A? or SL(?,?). Then we ? and |?(G)| = ?. Then G is q-nilpotent for some prime q. So G = [P] Q where P = Op(G) for some prime p ? q, and the Sylow q-subgroup Q = ?x? of G is cyclic. Let (Q ) ?=Q/(CQ(P)) .