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A284609
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Number of partitions of n such that the (sum of all odd parts) = floor(n/2).
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1
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0, 0, 1, 1, 0, 0, 4, 4, 0, 0, 9, 12, 0, 0, 25, 30, 0, 0, 56, 70, 0, 0, 132, 165, 0, 0, 270, 330, 0, 0, 594, 704, 0, 0, 1140, 1380, 0, 0, 2268, 2688, 0, 0, 4256, 4984, 0, 0, 8008, 9394, 0, 0, 14342, 16665, 0, 0, 25920, 29970, 0, 0, 45056, 52096
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OFFSET
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1,7
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COMMENTS
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Consequently the sum of all even parts is ceiling(n/2). Therefore, a(4n + 1) = a(4n + 2) = 0. - David A. Corneth, Apr 02 2017
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LINKS
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EXAMPLE
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a(8) counts these 4 partitions: 431, 3221, 32111, 311111.
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MATHEMATICA
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Table[p = IntegerPartitions[n]; Length[Select[
Table[Total[Select[DeleteDuplicates[p[[k]]], EvenQ]], {k,
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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