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A324587
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Heinz numbers of integer partitions of n into distinct perfect squares (A033461).
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8
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1, 2, 7, 14, 23, 46, 53, 97, 106, 151, 161, 194, 227, 302, 311, 322, 371, 419, 454, 541, 622, 661, 679, 742, 827, 838, 1009, 1057, 1082, 1193, 1219, 1322, 1358, 1427, 1589, 1619, 1654, 1879, 2018, 2114, 2143, 2177, 2231, 2386, 2437, 2438, 2741, 2854, 2933
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OFFSET
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1,2
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COMMENTS
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The Heinz number of an integer partition (y_1, ..., y_k) is prime(y_1) * ... * prime(y_k).
Also products of distinct elements of A011757.
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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: {}
2: {1}
7: {4}
14: {1,4}
23: {9}
46: {1,9}
53: {16}
97: {25}
106: {1,16}
151: {36}
161: {4,9}
194: {1,25}
227: {49}
302: {1,36}
311: {64}
322: {1,4,9}
371: {4,16}
419: {81}
454: {1,49}
541: {100}
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MATHEMATICA
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Select[Range[1000], And@@Cases[FactorInteger[#], {p_, k_}:>k==1&&IntegerQ[Sqrt[PrimePi[p]]]]&]
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CROSSREFS
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Cf. A001156, A005117, A011757, A033461, A052335, A056239, A062457, A078135, A112798, A117144, A276078.
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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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