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A284898
Expansion of Product_{k>=1} 1/(1+x^k)^(k^4) in powers of x.
5
1, -1, -15, -66, -54, 725, 4580, 12739, 3346, -149076, -791226, -2182124, -1656973, 16553206, 100646954, 318795473, 506196578, -818806580, -9148048880, -36415709566, -87180585636, -70923559814, 484810027389, 2992082912770, 9866919438716, 19936695359140
OFFSET
0,3
LINKS
FORMULA
a(0) = 1, a(n) = -(1/n)*Sum_{k=1..n} A284926(k)*a(n-k) for n > 0. - Seiichi Manyama, Apr 06 2017
MATHEMATICA
CoefficientList[Series[Product[1/(1 + x^k)^(k^4) , {k, 40}], {x, 0, 40}], x] (* Indranil Ghosh, Apr 05 2017 *)
PROG
(PARI) x= 'x + O('x^40); Vec(prod(k=1, 40, 1/(1 + x^k)^(k^4))) \\ Indranil Ghosh, Apr 05 2017
CROSSREFS
Cf. A248883.
Product_{k>=1} 1/(1+x^k)^(k^m): A081362 (m=0), A255528 (m=1), A284896 (m=2), A284897 (m=3), this sequence (m=4), A284899 (m=5).
Sequence in context: A090026 A027526 A334802 * A033653 A088058 A062392
KEYWORD
sign
AUTHOR
Seiichi Manyama, Apr 05 2017
STATUS
approved