proposition: Lemma ucn_group_set gT (G : {group gT}) : group_set 'Z_n(G).
proof: Proof. by have [hZ ->] := ucn_pmap; apply: groupP. Qed.
imports: mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq path) mathcomp(fintype div bigop prime finset fingroup morphism) mathcomp(automorphism quotient commutator gproduct) mathcomp(gfunctor center gseries cyclic)