(1) Department of Mathematics, Hubei University, Wuhan, Hubei, 430062, P.R. China
Abstract:
This paper shows that if is a semidirect product of finite groups, then if and only if and for all . As an application, we investigate the automorphism group of a split metacyclic p-group for odd p.
The second author is supported by the Natural Science Foundation of China (10671058).