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A226934
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Numbers k such that tau(2k) | sigma(2k).
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1
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3, 7, 10, 11, 15, 19, 21, 22, 23, 27, 28, 30, 31, 33, 34, 35, 39, 43, 46, 47, 48, 51, 55, 57, 58, 59, 63, 66, 67, 69, 70, 71, 75, 77, 79, 82, 83, 84, 87, 91, 92, 93, 94, 95, 99, 102, 103, 105, 106, 107, 110, 111, 112
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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Select[ Range[120], Divisible[ DivisorSigma[1, 2*#], DivisorSigma[0, 2*#]] &] (* Jean-François Alcover, Jul 03 2013 *)
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PROG
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(PARI) is_a226394(n) = (sigma(2*n, 1) % sigma(2*n, 0) == 0) \\ Michael B. Porter, Jun 27 2013
(Magma) [n: n in [1..120] | IsZero(SumOfDivisors(2*n) mod NumberOfDivisors(2*n))]; // Bruno Berselli, Jun 28 2013
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CROSSREFS
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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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