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A285675
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Expansion of Product_{n>0} ((1-x^n)/(1+x^n))^n in powers of x.
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5
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1, -2, -2, 0, 6, 8, 4, -4, -18, -34, -32, -8, 36, 96, 144, 152, 94, -60, -294, -560, -760, -760, -460, 228, 1276, 2486, 3576, 4080, 3456, 1304, -2576, -7956, -13986, -19208, -21644, -19056, -9462, 8200, 33364, 63224, 92384, 112860, 114976, 88896, 26660, -74792
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OFFSET
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0,2
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LINKS
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FORMULA
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a(0) = 1, a(n) = -(2/n)*Sum_{k=1..n} A076577(k)*a(n-k) for n > 0.
G.f.: exp(Sum_{k>=1} (sigma_2(k) - sigma_2(2*k))*x^k/(2*k)). - Ilya Gutkovskiy, Apr 14 2019
G.f.: exp( - 2*Sum_{n >= 0} x^(2*n+1)/((2*n+1)*(1 - x^(2*n+1))^2) ). Cf. A000122. - Peter Bala, Dec 23 2021
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CROSSREFS
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KEYWORD
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sign
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AUTHOR
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STATUS
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approved
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