OFFSET
0,3
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..284
FORMULA
a(n) = [x^n] Sum_{k>=0} x^k/(1 - n*k * x).
a(n) ~ sqrt(2*Pi/(n*(1 + LambertW(exp(1)*n^2)))) * (n^2/LambertW(exp(1)*n^2))^(n + 1/2 - n/LambertW(exp(1)*n^2)). - Vaclav Kotesovec, Dec 07 2021
MATHEMATICA
a[n_] := Sum[If[k == n == 0, 1, (k*n)^(n - k)], {k, 0, n}]; Array[a, 19, 0] (* Amiram Eldar, Dec 07 2021 *)
PROG
(PARI) a(n) = sum(k=0, n, (k*n)^(n-k));
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Dec 07 2021
STATUS
approved