OFFSET
1,2
COMMENTS
What is the limit_{n->infinity} a(n) / (n*log(n)/LambertW(log(n))) ?. - Vaclav Kotesovec, Aug 30 2021
LINKS
Seiichi Manyama, Table of n, a(n) for n = 1..10000
Vaclav Kotesovec, Plot of a(n) / (n*log(n)/LambertW(log(n))) for n = 1..10000
FORMULA
G.f.: (1/(1 - x)) * Sum_{k>=1} k^k * x^(k^k)/(1 - x^(k^k)).
MATHEMATICA
Table[Sum[k^k*Floor[n/k^k], {k, 1, n}], {n, 1, 100}] (* Vaclav Kotesovec, Aug 30 2021 *)
PROG
(PARI) a(n) = sum(k=1, n, k^k*(n\k^k));
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Aug 30 2021
STATUS
approved