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A320279
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Number of partitions of 2*n into parts that are the average of twin prime pairs (A014574).
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0
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1, 0, 1, 1, 1, 1, 3, 1, 3, 4, 3, 4, 7, 4, 7, 10, 7, 10, 15, 10, 15, 21, 15, 21, 29, 21, 29, 39, 29, 39, 53, 39, 53, 68, 53, 68, 91, 68, 91, 114, 91, 114, 148, 114, 148, 184, 148, 184, 232, 184, 232, 287, 232, 287, 355, 287, 355, 434, 355, 434, 531, 434, 531, 641, 531, 641
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OFFSET
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0,7
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LINKS
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FORMULA
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a(n) = [x^(2*n)] Product_{k>=1} 1/(1 - x^A014574(k)).
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EXAMPLE
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a(10) = 3 because we have [12, 4, 4], [6, 6, 4, 4] and [4, 4, 4, 4, 4].
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MATHEMATICA
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nmax = 65; Table[CoefficientList[Series[Product[1/(1 - Boole[PrimeQ[k + 1] && PrimeQ[k - 1]] x^k), {k, 1, 2 nmax}], {x, 0, 2 nmax}], x][[n]], {n, 1, 2 nmax + 1, 2}]
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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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