proposition: Lemma conjsg_eq1 A x : (A :^ x == 1%g) = (A == 1%g).
proof: Proof. by rewrite (canF_eq (conjsgK x)) conjs1g. Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq choice) mathcomp(fintype div path tuple bigop prime finset)