(** * The list of integers between 1 and n (inclusive) *)
Fixpoint until (n : nat) : Zlist :=
match n with
| O => Nil Z
| S n => Cons Z (Z_of_nat (S n)) (until n)
end.

Lemma until_nodoubles1 :
forall p : nat, Prime p -> forall n : nat, n < p -> nodoubles p (until n).