proposition: Lemma sternD_middle_contra' n k : nth 0 (stern11 n.+1) k = 2 -> k = 2 ^ n.
proof: Proof. by apply:sternD_middle_contra. 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)