OFFSET
1,2
LINKS
Seiichi Manyama, Table of n, a(n) for n = 1..2096
FORMULA
G.f.: Sum_{n>=1} -log(1 - (n^3)*x^n)/n = Sum_{n>=1} a(n) x^n/n.
G.f.: Sum_{k>=1} k^3*x^k/(1-k^3*x^k). - Benoit Cloitre, Apr 21 2003
EXAMPLE
a(10) = (10/1)^(3*1) +(10/2)^(3*2) +(10/5)^(3*5) +(10/10)^(3*10) = 49394 because positive divisors of 10 are 1, 2, 5, 10.
MATHEMATICA
Table[Total[Quotient[n, x = Divisors[n]]^(3*x)], {n, 27}] (* Jayanta Basu, Jul 08 2013 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Paul D. Hanna, Aug 04 2002
STATUS
approved