proposition: Lemma FM_cE n: FMc (n.+1) = (FMd n).*2.+1.
proof: Proof. by rewrite /= (surjective_pairing (Fib_fusc_rec n)). 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)