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A096738
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Numbers n such that A096736(n) = (n*tau(n)-1)/(tau(n)-1).
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3
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2, 3, 5, 7, 9, 10, 11, 13, 17, 19, 22, 23, 25, 29, 31, 34, 37, 41, 43, 46, 47, 49, 53, 55, 58, 59, 61, 67, 71, 73, 76, 78, 79, 81, 82, 83, 85, 89, 91, 94, 97, 101, 103, 106, 107, 109, 113, 115, 116, 118, 121, 127, 131, 133, 137, 139, 142, 145, 149, 151, 157, 163
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OFFSET
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1,1
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COMMENTS
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(a(n)*tau(a(n))-1) mod (tau(a(n))-1) = 0;
primes are a subsequence.
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LINKS
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MATHEMATICA
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Select[Range[2, 500], (#*DivisorSigma[0, #] - 1)/(DivisorSigma[0, #] - 1) == Floor[(#*DivisorSigma[0, #] - 1)/(DivisorSigma[0, #] - 1)] &] (* G. C. Greubel, Nov 28 2016 *)
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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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