proposition: Theorem make_listto3irI k c l1 l2 ll : In k ll -> In k (to3it _ make_list l1 l2 ll c).
proof: Proof. intro H; replace ll with (ll ++ nil); try rewrite make_listto3irA; auto with datatypes. Qed.
imports: PrimInt63 Cyclic63 List BasicRubik