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A240127
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Number of partitions of n such that the sum of squares of the parts is a square.
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2
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1, 1, 1, 2, 2, 1, 3, 3, 3, 5, 5, 6, 10, 9, 10, 17, 20, 18, 31, 34, 38, 52, 62, 65, 98, 108, 113, 160, 190, 204, 271, 322, 352, 448, 533, 572, 757, 863, 956, 1208, 1401, 1555, 1931, 2242, 2499, 3034, 3527, 3938, 4772, 5529, 6108, 7368, 8524, 9478, 11301
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OFFSET
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1,4
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LINKS
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EXAMPLE
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a(12) counts these 6 partitions: [12], [5,2,2,1,1,1], [4,4,1,1,1,1], [4,3,3,1,1], [3,3,3,3], [2,2,1,1,1,1,1,1,1,1].
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MATHEMATICA
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f[x_] := x^(1/2); z = 26; ColumnForm[t = Map[Select[IntegerPartitions[#], IntegerQ[f[Total[#^2]]] &] &, Range[z]] ](* shows the partitions *)
t2 = Map[Length[Select[IntegerPartitions[#], IntegerQ[f[Total[#^2]]] &]] &, Range[40]] (* A240127 *) (* Peter J. C. Moses, Apr 01 2014 *)
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PROG
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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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