proposition: Lemma shape_yamtab sh : shape (yamtab sh) = sh.
proof: Proof. rewrite /yamtab; move: (0) => i. elim: sh i => [//= | s0 sh IHsh] /= i. by rewrite size_nseq IHsh. Qed.
imports: mathcomp.ssreflect.ssreflect mathcomp(ssrfun ssrbool eqtype ssrnat seq fintype) mathcomp(tuple finfun finset path bigop order) tools partition Yamanouchi ordtype std tableau stdtab Schensted congr plactic Greene_inv stdplact