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Search: id:A113837
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| A113837 |
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A number n is included if d(sigma(n)) > sigma(d(n)), where d(n) is number of positive divisors of n, and sigma(n) is sum of positive divisors of n. |
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1
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| 5, 7, 11, 13, 14, 15, 17, 19, 22, 23, 26, 27, 29, 31, 33, 34, 35, 37, 38, 39, 41, 43, 46, 47, 51, 53, 54, 55, 56, 57, 58, 59, 61, 62, 65, 67, 69, 71, 73, 74, 77, 78, 79, 82, 83, 85, 86, 87, 88, 89, 91, 92, 93, 94, 95, 97, 101, 102, 103, 104, 106, 107, 109, 110, 111, 113, 114
(list; graph; listen)
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OFFSET
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1,1
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EXAMPLE
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d(sigma(14)) = d(24) = 8. And sigma(d(14)) = sigma(4) = 7. Since 8 > 7, 14 is in the sequence.
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MAPLE
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with(numtheory): a:=proc(n) if tau(sigma(n))>sigma(tau(n)) then n else fi end: seq(a(n), n=1..122); - Emeric Deutsch (deutsch(AT)duke.poly.edu), Feb 06 2006
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CROSSREFS
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Cf. A062068, A062069.
Sequence in context: A082684 A096379 A098761 this_sequence A079498 A035035 A113909
Adjacent sequences: A113834 A113835 A113836 this_sequence A113838 A113839 A113840
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KEYWORD
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nonn
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AUTHOR
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Leroy Quet (qq-quet(AT)mindspring.com), Jan 23 2006
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EXTENSIONS
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More terms from Emeric Deutsch (deutsch(AT)duke.poly.edu), Feb 06 2006
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