fact: Definition prime_idealr_closed (R : ringType) (S : {pred R}) : Prop := forall u v, u * v \in S -> (u \in S) || (v \in S).
imports: HB(structures) mathcomp(ssreflect eqtype choice ssreflect ssrbool ssrnat) mathcomp(ssrfun seq ssralg generic_quotient)