proposition: Lemma log2_pow n: log2 (2^ n) = n.+1.
proof: Proof. by apply:log2_pr; rewrite leqnn ltn_exp2l /=. 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)