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A294757
Expansion of Product_{k>=1} 1/(1 - k^k*x^k)^(k^k).
4
1, 1, 17, 746, 66442, 9843731, 2187951485, 680615166718, 282199710311343, 150389915850565698, 100155578811552469018, 81505577529171038120173, 79580089696277797740768316, 91814299717377746850767747558
OFFSET
0,3
COMMENTS
This sequence is obtained from the generalized Euler transform in A266964 by taking f(n) = g(n) = n^n.
LINKS
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
PROG
(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
CROSSREFS
Column k=1 of A294756.
Sequence in context: A218423 A171766 A283579 * A176233 A360647 A355495
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Nov 08 2017
STATUS
approved