2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/79608Permutations avoiding all patterns of a given shape (in the sense of Robinson-Schensted-Knuth) are considered. We show that the shapes of all such permutations are contained in a suitable thick hook, and deduce an exponential growth rate for their number.16 pages; final form, to appear in J. Combin. Theory, Series ACombinatoricstext