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A356689
a(n) = n! * Sum_{k=0..n} k^(k*n)/k!.
2
1, 2, 20, 19887, 4297096180, 298028721722131825, 10314430386434427534836297166, 256923580889667624113335512704714686054849, 6277101737079381675512518990977258744796239498871290255000
OFFSET
0,2
LINKS
FORMULA
E.g.f.: Sum_{k>=0} (k^k * x)^k / (k! * (1 - k^k * x)).
PROG
(PARI) a(n) = n!*sum(k=0, n, k^(k*n)/k!);
(PARI) my(N=10, x='x+O('x^N)); Vec(serlaplace(sum(k=0, N, (k^k*x)^k/(k!*(1-k^k*x)))))
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Aug 23 2022
STATUS
approved