A294757 Expansion of Product_{k>=1} 1/(1 - k^k*x^k)^(k^k).
1, 1, 17, 746, 66442, 9843731, 2187951485, 680615166718, 282199710311343, 150389915850565698, 100155578811552469018, 81505577529171038120173, 79580089696277797740768316, 91814299717377746850767747558
Offset: 0
Keywords
Links
- Seiichi Manyama, Table of n, a(n) for n = 0..214
Programs
-
PARI
N=20; x='x+O('x^N); Vec(1/prod(k=1, N, (1-k^k*x^k)^k^k))
-
PARI
sd(n) = sumdiv(n, d, d^(d+n+1)); a(n) = if (n==0, 1, sum(k=1, n, sd(k)*a(n-k))/n); \\ Michel Marcus, Nov 10 2017
Formula
a(0) = 1 and a(n) = (1/n) * Sum_{k=1..n} A294773(k)*a(n-k) for n > 0.
a(n) ~ n^(2*n). - Vaclav Kotesovec, Nov 08 2017
Comments