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Search: id:A100592
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| A100592 |
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Least positive integer that can be represented as the sum of exactly two semiprimes in exactly n ways. |
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+0
2
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| 1, 8, 18, 30, 43, 48, 60, 72, 91, 108, 132, 155, 120, 144, 192, 168, 216, 236, 227, 180, 320, 340, 240, 252, 348, 300, 324, 336, 488, 484, 456, 396, 614, 360, 524, 548, 706, 468, 536, 656, 628, 420, 624, 576, 612, 588, 540, 600, 648, 768, 732, 800, 832, 660
(list; graph; listen)
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OFFSET
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0,2
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FORMULA
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a(n) = min{i such that i = A001358(j) + A001358(k) in n ways}.
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EXAMPLE
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a(0) = 1 because 1 is the smallest positive integer that cannot be represented as sum of two semiprimes (since 4 is the smallest semiprime). a(1) = 8 because 8 is the smallest such sum of two semiprimes: 4 + 4. Similarly a(2) = 18 because 18 = 14 + 4 = 9 + 9 where {4,9,14} are semiprimes and there is no third such sum for 18.
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CROSSREFS
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Cf. A001358, A076768, A100570, A072966.
Sequence in context: A084394 A085248 A092163 this_sequence A028563 A120091 A098944
Adjacent sequences: A100589 A100590 A100591 this_sequence A100593 A100594 A100595
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KEYWORD
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easy,nonn
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AUTHOR
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Jonathan Vos Post (jvospost3(AT)gmail.com), Nov 30 2004
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