proposition: Lemma quotient_pgroup : pi.-group (K / H).
proof: Proof. exact: morphim_pgroup. Qed.
imports: mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq div) mathcomp(fintype bigop finset prime fingroup morphism) mathcomp(gfunctor automorphism quotient action gproduct) mathcomp(cyclic)