proposition: Lemma consttV pi x : (x^-1).`_pi = (x.`_pi)^-1.
proof: Proof. by rewrite /constt expgVn orderV. 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)