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A091901
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Values of n for which sigma(n) < e^gamma * n * log(log(n)).
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5
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7, 11, 13, 14, 15, 17, 19, 21, 22, 23, 25, 26, 27, 28, 29, 31, 32, 33, 34, 35, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 85, 86, 87, 88, 89
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OFFSET
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1,1
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COMMENTS
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sigma(n) < e^gamma * n * log(log(n)) is "Robin's inequality" - see A067698. Sequence is cofinite if and only if the Riemann Hypothesis is true.
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LINKS
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FORMULA
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MATHEMATICA
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Select[Range[100], DivisorSigma[1, #] < E^EulerGamma*#*Log[Log[#]] &] (* Jean-François Alcover, Oct 30 2012 *)
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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