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A316888
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Heinz numbers of aperiodic integer partitions into relatively prime parts whose reciprocal sum is 1.
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17
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2, 195, 3185, 6475, 10527, 16401, 20445, 20535, 21045, 25365, 46155, 164255, 171941, 218855, 228085, 267883, 312785, 333925, 333935, 335405, 343735, 355355, 414295, 442975, 474513, 527425, 549575, 607475, 633777, 691041, 711321, 722425, 753865, 804837, 822783
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OFFSET
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1,1
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COMMENTS
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The reciprocal sum of (y_1, ..., y_k) is 1/y_1 + ... + 1/y_k.
The Heinz number of an integer partition (y_1, ..., y_k) is prime(y_1) * ... * prime(y_k).
A partition is aperiodic if its multiplicities are relatively prime.
Does not contain 29888089, which belongs to A316890 and is the Heinz number of a periodic partition.
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LINKS
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EXAMPLE
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The partition (6,4,4,3) with Heinz number 3185 is aperiodic, has relatively prime parts, and 1/6 + 1/4 + 1/4 + 1/3 = 1, so 3185 belongs to the sequence.
The sequence of partitions whose Heinz numbers belong to the sequence begins: (1), (6,3,2), (6,4,4,3), (12,4,3,3), (10,5,5,2), (20,5,4,2), (15,10,3,2), (12,12,3,2), (18,9,3,2), (24,8,3,2), (42,7,3,2).
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MATHEMATICA
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Select[Range[2, 100000], And[GCD@@FactorInteger[#][[All, 2]]==1, GCD@@PrimePi/@FactorInteger[#][[All, 1]]==1, Sum[m[[2]]/PrimePi[m[[1]]], {m, FactorInteger[#]}]==1]&]
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CROSSREFS
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Cf. A000837, A002966, A007916, A051908, A100953, A289509, A296150, A316855, A316856, A316857, A316888-A316904.
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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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