%I #9 Jul 27 2023 16:53:32
%S 1,1,1,35,5392,35462624,15419509448256,445352317449860352384,
%T 1733058447330128629281872412672,
%U 1124641798042952855847954946807366969982976,155064212713307814902013200520441969883490549760000000000
%N a(n) = (n!)^n * [x^n] Product_{n>=1} (1 + x^k/k^n).
%H Alois P. Heinz, <a href="/A336306/b336306.txt">Table of n, a(n) for n = 0..31</a>
%p b:= proc(n, i, k) option remember; `if`(i*(i+1)/2<n, 0, `if`(n=0, 1,
%p b(n, i-1, k)+b(n-i, min(n-i, i-1), k)*((i-1)!*binomial(n, i))^k))
%p end:
%p a:= n-> b(n$3):
%p seq(a(n), n=0..12); # _Alois P. Heinz_, Jul 27 2023
%t Table[(n!)^n SeriesCoefficient[Product[(1 + x^k/k^n), {k, 1, n}], {x, 0, n}], {n, 0, 10}]
%Y Cf. A007838, A326864, A326865, A336294, A336295.
%K nonn
%O 0,4
%A _Ilya Gutkovskiy_, Jul 17 2020