proposition: Lemma mmax_norm X M : M \in 'M -> X :!=: 1 -> X \proper G -> M \subset 'N(X) -> 'N(X) = M.
proof: Proof. by move=> maxM ntX prX; apply: mmax_max (mFT_norm_proper _ _). Qed.
imports: HB(structures) mathcomp.ssreflect.ssreflect mathcomp(ssrbool ssrfun eqtype ssrnat seq div choice fintype bigop) mathcomp(finset prime fingroup morphism automorphism action quotient) mathcomp(gfunctor cyclic pgroup center commutator gseries nilpotent) mathcomp(sylow abelian maximal hall) odd_order(BGsection1 BGsection6)