Quasi-powerful -groups
arXiv:1912.08906
Abstract
In this paper we introduce the notion of a quasi-powerful -group for odd primes . These are the finite -groups such that is powerful in the sense of Lubotzky and Mann. We show that this large family of groups shares many of the same properties as powerful -groups. For example, we show that they have a regular power structure, and we generalise a result of Fernández-Alcober on the order of commutators in powerful -groups to this larger family of groups. We also obtain a bound on the number of generators of a subgroup of a quasi-powerful -group, expressed in terms of the number of generators of the group. We give an infinite family of examples which demonstrates this bound is close to best possible.