proposition: Lemma shape_stdtab_of_yam y : shape (stdtab_of_yam y) = evalseq y.
proof: Proof. elim: y => [// | y0 y IHy] /=. by rewrite shape_append_nth IHy. Qed.
imports: HB(structures) mathcomp(all_ssreflect) mathcomp(perm fingroup) tools combclass partition Yamanouchi ordtype std tableau