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A285991
Expansion of Product_{n>0} ((1-x^n)/(1+x^n))^(n^4) in powers of x.
3
1, -2, -30, -100, 262, 3672, 13836, -80, -264810, -1421438, -3019032, 7630764, 89648580, 358974280, 548677872, -2390377936, -20531491146, -74635378020, -110275527170, 425036176572, 3669041188152, 13597190512480, 23995331740700, -45340748171760
OFFSET
0,2
FORMULA
a(0) = 1, a(n) = -(2/n)*Sum_{k=1..n} A096960(k)*a(n-k) for n > 0.
G.f.: exp(Sum_{k>=1} (sigma_5(k) - sigma_5(2*k))*x^k/(16*k)). - Ilya Gutkovskiy, Apr 14 2019
CROSSREFS
Product_{n>0} ((1-x^n)/(1+x^n))^(n^m): A002448 (m=0), A285675 (m=1), A285988 (m=2), A285990 (m=3), this sequence (m=4).
Sequence in context: A085637 A193177 A157870 * A078838 A267851 A089288
KEYWORD
sign
AUTHOR
Seiichi Manyama, Apr 30 2017
STATUS
approved