fact: Definition S1 := (S :&: [set j : 'I_(size x) | j <= posa]) :|: (T :&: [set j : 'I_(size x) | j > posc]).
imports: mathcomp(all_ssreflect) mathcomp(perm) tools ordcast ordtype subseq partition tableau Yamanouchi stdtab Schensted congr plactic Greene