proposition: Lemma FM_recd: [/\ FMd 0 = 0, FMd 1 = 0 & forall n, FMd (n.+2) = FMd (n.+1) + (FMd n).*2.+1].
proof: Proof. by split => // n; rewrite FM_dE FM_cE addnC. 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)