fact: Definition join_Young_fun sh1 sh2 := [seq maxn a.1 a.2 | a <- zip (pad 0 (maxn (size sh1) (size sh2)) sh1) (pad 0 (maxn (size sh1) (size sh2)) sh2)].
imports: HB(structures) mathcomp(all_ssreflect) mathcomp(div ssralg ssrint ssrnum binomial) tools combclass sorted ordtype