A244298 Number of standard Young tableaux with n cells such that the lengths of the first and the last row differ by 4.

5, 15, 119, 421, 2254, 8999, 40349, 166817, 737829, 3008774, 13186593, 54944783, 238422808, 1010671048, 4395831546, 18821162274, 82799233661, 359711480525, 1599420076729, 7030074945271, 31626819884986, 141486845119777, 646988113794544, 2940338763342920

Offset: 6

Author

Joerg Arndt and Alois P. Heinz, Jun 25 2014

Keywords

• nonn

Comments

Also the number of ballot sequences of length n such that the multiplicities of the largest and the smallest value differ by 4.

Links

• Alois P. Heinz, Table of n, a(n) for n = 6..100

Crossrefs

Column k=4 of A238707.

Programs

Maple

h:= proc(l) local n; n:=nops(l); add(i, i=l)!/mul(mul(1+l[i]-j+
    add(`if`(l[k]>=j, 1, 0), k=i+1..n), j=1..l[i]), i=1..n) end:
g:= proc(n, i, l) local j; `if`(n=0 or i<1, 0, `if`(l<>[] and
      l[1]-i=4, `if`(irem(n, i, 'j')=0, h([l[], i$j]), 0),
      add(g(n-i*j, i-1, [l[], i$j]), j=0..n/i)))
    end:
a:= n-> g(n$2, []):
seq(a(n), n=6..35);

Mathematica

h[l_] := With[{n = Length[l]}, Total[l]!/Product[Product[1 + l[[i]] - j + Sum[If[l[[k]] >= j, 1, 0], {k, i + 1, n}], {j, l[[i]]}], {i, n}]];
g[n_, i_, l_] := Module[{j}, If[n == 0 || i < 1, 0, If[l != {} && l[[1]] - i == 4, If[j = Quotient[n, i]; Mod[n, i] == 0, h[Join[l, Table[i, {j}]]], 0], Sum[g[n - i*j, i - 1, Join[l, Table[i, {j}]]], {j, 0, n/i}]]]];
a[n_] := g[n, n, {}];
Table[a[n], {n, 6, 35}] (* Jean-François Alcover, Aug 28 2021, after Maple code *)