fact: Definition nilpotent := [forall (G : {group gT} | G \subset A :&: [~: G, A]), G :==: 1].
imports: mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq path) mathcomp(fintype div bigop prime finset fingroup morphism) mathcomp(automorphism quotient commutator gproduct) mathcomp(gfunctor center gseries cyclic)