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A366322
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Heinz numbers of integer partitions containing at least one odd part. Numbers divisible by at least one prime of odd index.
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10
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2, 4, 5, 6, 8, 10, 11, 12, 14, 15, 16, 17, 18, 20, 22, 23, 24, 25, 26, 28, 30, 31, 32, 33, 34, 35, 36, 38, 40, 41, 42, 44, 45, 46, 47, 48, 50, 51, 52, 54, 55, 56, 58, 59, 60, 62, 64, 65, 66, 67, 68, 69, 70, 72, 73, 74, 75, 76, 77, 78, 80, 82, 83, 84, 85, 86
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OFFSET
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1,1
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COMMENTS
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The Heinz number of a partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k). This gives a bijective correspondence between positive integers and integer partitions.
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LINKS
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FORMULA
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EXAMPLE
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The terms together with their prime indices begin:
2: {1}
4: {1,1}
5: {3}
6: {1,2}
8: {1,1,1}
10: {1,3}
11: {5}
12: {1,1,2}
14: {1,4}
15: {2,3}
16: {1,1,1,1}
17: {7}
18: {1,2,2}
20: {1,1,3}
22: {1,5}
23: {9}
24: {1,1,1,2}
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MATHEMATICA
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Select[Range[100], Or@@OddQ/@PrimePi/@First/@FactorInteger[#]&]
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CROSSREFS
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Partitions of this type are counted by A086543.
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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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