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A289350
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Coefficients in expansion of E_2/Product_{k>=1} (1-q^k)^2.
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0
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1, -22, -115, -350, -940, -2124, -4615, -9130, -17575, -32100, -57239, -98512, -166595, -274350, -445055, -708124, -1112002, -1719410, -2629450, -3970230, -5937238, -8785502, -12889630, -18741250, -27045445, -38724088, -55074057, -77791320, -109215025
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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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G.f.: Product_{k>=1} (1-q^k)^(A288995(k)/12).
a(n) ~ -3^(1/4) * exp(2*Pi*sqrt(n/3)) / n^(1/4). - Vaclav Kotesovec, Jul 08 2017
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MATHEMATICA
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nmax = 50; CoefficientList[Series[(1 - 24*Sum[DivisorSigma[1, k]*x^k, {k, 1, nmax}]) / Product[(1 - x^k)^2, {k, 1, nmax}], {x, 0, nmax}], x] (* Vaclav Kotesovec, Jul 08 2017 *)
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CROSSREFS
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E_2^(m/2)/Product_{k>=1} (1-q^k)^m: A289344 (m=1), this sequence (m=2), A289062 (m=24).
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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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