Abstract
We give in this note some new bounds on pc(G) in terms of σcfor several classes of finite groups, in particular, we prove that ρc≤4σc(G) for any finite solvable group G, which improves some known results. We also pose some related open problems.
1991 Mathematics Subject Classification:
Notes
*1991 Mathematics Subject Classification. 20D60. Supported in part by AvH, NSFC, TCTPFT2395