OFFSET
0,3
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..27
FORMULA
a(n) = A260876(n,n).
a(n) = (n^2)! * [x^(n^2)] exp(Sum_{k>=1} x^(n*k) / (n*k)!). - Ilya Gutkovskiy, Feb 09 2020
MAPLE
b:= proc(n, k) option remember; `if`(n=0, 1, add(
binomial(k*n-1, k*j-1)*b(n-j, k), j=1..n))
end:
a:= n-> b(n$2):
seq(a(n), n=0..10); # Alois P. Heinz, Aug 14 2019
MATHEMATICA
b[n_, k_] := b[n, k] = If[n == 0, 1, Sum[Binomial[k n - 1, k j - 1] b[n - j, k], {j, 1, n}]];
a[n_] := b[n, n];
a /@ Range[0, 10] (* Jean-François Alcover, Nov 07 2020, after Maple *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Peter Luschny, Aug 13 2019
STATUS
approved