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A265758
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Expansion of Product_{k>=1} ((1 + k*x^k)/(1 - k*x^k)).
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9
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1, 2, 6, 16, 38, 88, 200, 428, 902, 1874, 3780, 7504, 14732, 28368, 54052, 101960, 189750, 349996, 640218, 1159624, 2084952, 3722008, 6593560, 11606268, 20308188, 35312170, 61065636, 105060200, 179795936, 306244136, 519291476, 876554860, 1473504846
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OFFSET
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0,2
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COMMENTS
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LINKS
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FORMULA
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a(n) ~ c * 3^(n/3), where
c = 28711548.45004804552683870974706458425598... if mod(n,3) = 0
c = 28711547.74098394497470795294574937283075... if mod(n,3) = 1
c = 28711547.58138731567204220029302329316039... if mod(n,3) = 2.
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MATHEMATICA
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nmax = 40; CoefficientList[Series[Product[(1 + k*x^k)/(1 - k*x^k), {k, 1, nmax}], {x, 0, nmax}], x]
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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