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A069057
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Numbers k such that the numerator of Sum_{d|k} 1/d > 2k.
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3
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36, 100, 144, 324, 392, 400, 576, 784, 800, 900, 968, 1296, 1352, 1575, 1600, 1936, 2304, 2450, 2500, 2704, 2916, 3136, 3600, 3872, 4356, 4624, 5184, 5408, 5776, 6050, 6272, 6400, 7744, 8100, 8450, 8464, 9216, 9248, 10000, 10404, 10816, 11552, 11664
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OFFSET
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1,1
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COMMENTS
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Many terms in the sequence are squares: 6^2,10^2,12^2,18^2,20^2,24^2,28^2,30^2,36^2,40^2,44^2,48^2,50^2...
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LINKS
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MATHEMATICA
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Select[Range[12000], Numerator[Total[1/Divisors@ #]] > 2 # &] (* Michael De Vlieger, May 04 2016 *)
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PROG
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(PARI) isok(n) = numerator(sigma(n)/n) > 2*n; \\ Michel Marcus, May 04 2016
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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