proposition: Lemma joing1G G : 1 <*> G = G.
proof: Proof. by rewrite -gen0 joing_idl /joing set0U genGid. Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq choice) mathcomp(fintype div path tuple bigop prime finset)