(** Multiplication by a scalar *)
Section Properties3.
Context {K : AbsRing} {V : NormedModule K}.

(* Specifications: *)
Lemma is_series_scal (c : K) (a : nat -> V) (l : V) :
is_series a l -> is_series (fun n => scal c (a n)) (scal c l).
Lemma is_series_scal_l : forall (c : K) (a : nat -> V) (l : V),
is_series a l -> is_series (fun n => scal c (a n)) (scal c l).