proposition: Lemma fgzeroE k : fgzero@_k = 0.
proof: Proof. by rewrite mcoeff_fnd !(in_fsetE, not_fnd). Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat) mathcomp(seq path choice finset fintype finfun) mathcomp(tuple bigop ssralg ssrint ssrnum) xfinmap