A214722 Number A(n,k) of solid standard Young tableaux of shape [[{n}^k],[n]]; square array A(n,k), n>=0, k>=1, read by antidiagonals.
1, 1, 1, 1, 2, 2, 1, 3, 16, 5, 1, 4, 91, 192, 14, 1, 5, 456, 5471, 2816, 42, 1, 6, 2145, 143164, 464836, 46592, 132, 1, 7, 9724, 3636776, 75965484, 48767805, 835584, 429, 1, 8, 43043, 91442364, 12753712037, 55824699632, 5900575762, 15876096, 1430
Offset: 0
Examples
Square array A(n,k) begins: 1, 1, 1, 1, 1, 1, ... 1, 2, 3, 4, 5, 6, ... 2, 16, 91, 456, 2145, 9724, ... 5, 192, 5471, 143164, 3636776, 91442364, ... 14, 2816, 464836, 75965484, 12753712037, 2214110119572, ... 42, 46592, 48767805, 55824699632, 70692556053053, 98002078234748974, ...
Links
- Alois P. Heinz, Antidiagonals n = 0..20, flattened
- S. B. Ekhad, D. Zeilberger, Computational and Theoretical Challenges on Counting Solid Standard Young Tableaux, arXiv:1202.6229v1 [math.CO], 2012
- Wikipedia, Young tableau
Crossrefs
Programs
-
Maple
b:= proc(l) option remember; local m; m:= nops(l); `if`({map(x-> x[], l)[]}={0}, 1, add(add(`if`(l[i][j]> `if`(i=m or nops(l[i+1])
`if`(nops(l[i])=j, 0, l[i][j+1]), b(subsop(i=subsop( j=l[i][j]-1, l[i]), l)), 0), j=1..nops(l[i])), i=1..m)) end: A:= (n, k)-> b([[n$k], [n]]): seq(seq(A(n, 1+d-n), n=0..d), d=0..10); -
Mathematica
b[l_List] := b[l] = With[{m = Length[l]}, If[Union[Flatten[l]] == {0}, 1, Sum[Sum[If[l[[i, j]] > If[i == m || Length[l[[i+1]]] < j, 0, l[[i+1, j]]] && l[[i, j]] > If[Length[l[[i]]] == j, 0, l[[i, j+1]]], b[ReplacePart[l, i -> ReplacePart[l[[i]], j -> l[[i, j]] - 1]]], 0], {j, 1, Length[l[[i]]]}], {i, 1, m}]] ]; a[n_, k_] := b[{Array[n&, k], {n}}]; Table[Table[a[n, 1+d-n], {n, 0, d}], {d, 0, 10}] // Flatten (* Jean-François Alcover, Dec 17 2013, translated from Maple *)