#[global]
Instance CR_cv_morph
: forall {R : ConstructiveReals} (un : nat -> CRcarrier R), CMorphisms.Proper
(CMorphisms.respectful (CReq R) CRelationClasses.iffT) (CR_cv R un).

Lemma CR_cv_open_below
: forall {R : ConstructiveReals}
(un : nat -> CRcarrier R) (m l : CRcarrier R),
CR_cv R un l
-> m < l
-> { n : nat & forall i:nat, le n i -> m < un i }.