Fixpoint SubEquiN (N:nat) (x y:R) (del:posreal) : list R :=
  match N with
    | O => cons y nil
    | S p => cons x (SubEquiN p (x + del) y del)
  end.Definition max_N (a b:R) (del:posreal) (h:a < b) : nat :=
  let (N,_) := maxN del h in N.Definition SubEqui (a b:R) (del:posreal) (h:a < b) : list R :=
  SubEquiN (S (max_N del h)) a b del.

Lemma RiemannInt_P11 : forall (f:R -> R) (a b l:R) (un:nat -> posreal) (phi1 phi2 psi1 psi2:nat -> StepFun a b), Un_cv un 0 -> (forall n:nat, (forall t:R, Rmin a b <= t <= Rmax a b -> Rabs (f t - phi1 n t) <= psi1 n t) /\ Rabs (RiemannInt_SF (psi1 n)) < un n) -> (forall n:nat, (forall t:R, Rmin a b <= t <= Rmax a b -> Rabs (f t - phi2 n t) <= psi2 n t) /\ Rabs (RiemannInt_SF (psi2 n)) < un n) -> Un_cv (fun N:nat => RiemannInt_SF (phi1 N)) l -> Un_cv (fun N:nat => RiemannInt_SF (phi2 N)) l.