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A245398
Sum of n-th powers of coefficients in full expansion of (z_1 + z_2 + ... + z_n)^n.
3
1, 1, 6, 381, 591460, 41262262505, 207874071367118436, 110807909819808911886548575, 8558639841332633529404511878004186120, 124773193097402414339622625011223384066643153613969, 431220070110830123225191271755402469908417673177630594034899052340
OFFSET
0,3
LINKS
FORMULA
a(n) = [x^n] (n!)^n * (Sum_{j=0..n} x^j/(j!)^n)^n.
a(n) = A245397(n,n).
MAPLE
b:= proc(n, i, k) option remember; `if`(n=0 or i=1, 1,
add(b(n-j, i-1, k)*binomial(n, j)^k, j=0..n))
end:
a:= n-> b(n$3):
seq(a(n), n=0..12);
MATHEMATICA
b[n_, i_, k_] := b[n, i, k] = If[n == 0, 1, If[i < 1, 0,
Sum[b[n-j, i-1, k]*Binomial[n, j]^(k-1)/j!, {j, 0, n}]]];
a[n_] := n!*b[n, n, n];
Table[a[n], {n, 0, 12}] (* Jean-François Alcover, Jun 27 2022, after Alois P. Heinz *)
CROSSREFS
Main diagonal of A245397.
Sequence in context: A158041 A233212 A270558 * A078207 A261296 A060871
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Jul 21 2014
STATUS
approved