proposition: Lemma perm_mact a : actperm morph_action a = phi a.
proof: Proof. by apply/permP=> x; rewrite permE. Qed.
imports: mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat div seq) mathcomp(fintype bigop finset fingroup morphism perm) mathcomp(automorphism quotient)