proposition: Lemma odd_base2rev n: odd (base2rev n.+1).
proof: Proof. rewrite /base2rev nat_list_succ. by case: behead => // b l /=; rewrite odd_double. Qed.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat) mathcomp(seq choice fintype order bigop ssralg) mathcomp(div ssrnum ssrint rat prime path binomial) mathcomp(tuple finset) gaia(fibm)