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A298436
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Expansion of Product_{k>=1} 1/(1 - x^prime(k))^2.
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3
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1, 0, 2, 2, 3, 6, 7, 12, 15, 22, 30, 40, 54, 72, 93, 122, 157, 202, 256, 326, 409, 512, 640, 792, 981, 1204, 1479, 1802, 2196, 2662, 3218, 3880, 4660, 5588, 6677, 7960, 9471, 11232, 13299, 15710, 18514, 21784, 25570, 29968, 35047, 40922, 47698, 55500, 64480, 74786, 86618
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OFFSET
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0,3
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COMMENTS
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Number of partitions of n into prime parts of 2 kinds.
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LINKS
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FORMULA
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G.f.: Product_{k>=1} 1/(1 - x^prime(k))^2.
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EXAMPLE
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a(5) = 6 because we have [5a], [5b], [3a, 2a], [3a, 2b], [3b, 2a] and [3b, 2b].
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MATHEMATICA
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nmax = 50; CoefficientList[Series[Product[1/(1 - x^Prime[k])^2, {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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