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A318717
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Number of strict integer partitions of n in which no two parts are relatively prime.
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27
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1, 1, 1, 1, 1, 1, 2, 1, 2, 2, 3, 1, 5, 1, 5, 4, 6, 1, 10, 1, 11, 6, 12, 1, 19, 3, 18, 8, 23, 1, 36, 2, 32, 13, 38, 7, 57, 2, 54, 19, 68, 3, 95, 3, 90, 33, 104, 3, 148, 7, 149, 40, 166, 5, 230, 17, 226, 56, 256, 6, 360, 9, 340, 84, 390, 25, 527, 11, 513, 109
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OFFSET
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0,7
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LINKS
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EXAMPLE
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The a(20) = 11 partitions:
(20),
(12,8), (14,6), (15,5), (16,4), (18,2),
(10,6,4), (10,8,2), (12,6,2), (14,4,2),
(8,6,4,2).
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MATHEMATICA
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Table[Length[Select[IntegerPartitions[n], And[UnsameQ@@#, And@@(GCD[##]>1&)@@@Select[Tuples[#, 2], Less@@#&]]&]], {n, 30}]
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CROSSREFS
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Cf. A000009, A007359, A007360, A051185, A302569, A302797, A303140, A303280, A303283, A305713, A305843, A305854, A305713, A318715, A318719.
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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