proposition: Lemma GAr_big B m n: n <= B -> GAr B m n = GA m n.
proof: Proof. rewrite /GA => lnb; symmetry; apply:GAr_big0 => //. by rewrite (leq_ltn_trans (leqnSn n)(fib_gen n.+2)) orbT. Qed.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat) mathcomp(seq path fintype div bigop binomial) mathcomp(prime finset ssralg ssrnum ssrint)