proposition: Lemma semiringClosedP (rngS : semiringClosed R) : semiring_closed rngS.
proof: Proof. split; [ exact: rpred0D | exact: rpred1M ]. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div seq) mathcomp(choice fintype finfun bigop prime binomial)