proposition: Lemma conjg_set1 x y : [set x] :^ y = [set x ^ y].
proof: Proof. by rewrite [_ :^ _]imset_set1. Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq choice) mathcomp(fintype div path tuple bigop prime finset)