OFFSET
0,3
FORMULA
G.f.: Sum_{k>=0} k * x^k/(1 - k^k * x).
PROG
(PARI) a(n) = sum(k=0, n, k^(k*(n-k)+1));
(PARI) my(N=20, x='x+O('x^N)); concat(0, Vec(sum(k=0, N, k*x^k/(1-k^k*x))))
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Jan 10 2023
STATUS
approved