Definition series_cv {R : ConstructiveReals}
           (un : nat -> CRcarrier R) (s : CRcarrier R) : Set
  := CR_cv R (CRsum un) s.Definition series_cv_lim_lt {R : ConstructiveReals}
           (un : nat -> CRcarrier R) (x : CRcarrier R) : Set
  := { l : CRcarrier R & prod (series_cv un l) (l < x) }.Definition series_cv_le_lim {R : ConstructiveReals}
           (x : CRcarrier R) (un : nat -> CRcarrier R) : Set
  := { l : CRcarrier R & prod (series_cv un l) (x <= l) }.

Lemma series_cv_abs_lt : forall {R : ConstructiveReals} (un vn : nat -> CRcarrier R) (l : CRcarrier R), (forall n:nat, CRabs R (un n) <= vn n) -> series_cv_lim_lt vn l -> series_cv_lim_lt un l.