proposition: Lemma Frobenius_compl_Hall : Hall G H.
proof: Proof. have [defG _ _ _ _] := Frobenius_context. by rewrite -(sdprod_Hall defG) Frobenius_ker_Hall. Qed.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div) mathcomp(fintype bigop prime finset fingroup morphism) mathcomp(perm action quotient gproduct cyclic center) mathcomp(pgroup nilpotent sylow hall abelian)