proposition: Lemma Zeckp_fib n: Zeckp (fib n.+2) = fib n.+1.
proof: Proof. by rewrite /Zeckp Zeck_fib /Zeck_valp big_cons big_nil addn0. Qed.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat) mathcomp(seq path fintype div bigop binomial) mathcomp(prime finset ssralg ssrnum ssrint)