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A325700
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Numbers with as many distinct even as distinct odd prime indices.
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30
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1, 6, 12, 14, 15, 18, 24, 26, 28, 33, 35, 36, 38, 45, 48, 51, 52, 54, 56, 58, 65, 69, 72, 74, 75, 76, 77, 86, 93, 95, 96, 98, 99, 104, 106, 108, 112, 116, 119, 122, 123, 135, 141, 142, 143, 144, 145, 148, 152, 153, 158, 161, 162, 172, 175, 177, 178, 185, 192
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OFFSET
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1,2
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COMMENTS
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These are the Heinz numbers of the integer partitions counted by A241638.
A prime index of n is a number m such that prime(m) divides n. The multiset of prime indices of n is row n of A112798.
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LINKS
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EXAMPLE
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The sequence of terms together with their prime indices begins:
1: {}
6: {1,2}
12: {1,1,2}
14: {1,4}
15: {2,3}
18: {1,2,2}
24: {1,1,1,2}
26: {1,6}
28: {1,1,4}
33: {2,5}
35: {3,4}
36: {1,1,2,2}
38: {1,8}
45: {2,2,3}
48: {1,1,1,1,2}
51: {2,7}
52: {1,1,6}
54: {1,2,2,2}
56: {1,1,1,4}
58: {1,10}
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MATHEMATICA
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Select[Range[100], 0==Total[(-1)^PrimePi/@First/@If[#==1, {}, FactorInteger[#]]]&]
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CROSSREFS
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Cf. A001221, A026010, A028260, A045931, A063886, A097613, A112798, A130780, A239241, A241638, A325698, A325699.
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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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