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A272883
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Numbers n such that sigma_k(x) = n has no solution for any k > 0.
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1
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2, 11, 16, 19, 22, 23, 25, 27, 29, 34, 35, 37, 41, 43, 45, 46, 47, 49, 51, 52, 53, 55, 58, 59, 61, 64, 66, 67, 69, 70, 71, 75, 76, 77, 79, 81, 83, 86, 87, 88, 89, 92, 94, 95, 97, 99, 100, 101, 103, 105, 106, 107, 109, 111, 113, 115, 116, 117, 118, 119, 123, 125
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OFFSET
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1,1
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COMMENTS
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Recall that sigma_k(n) = Sum_{d|n} d^k.
Sigma_0(n), the number of divisors of n, can be any positive integer and so is ignored in this sequence.
Numbers n such that A271606(n) = 0.
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LINKS
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PROG
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(Magma) [n: n in [1..2^7] | [n] notsubset Set(Sort([DivisorSigma(k, n): n in [1..2^7+1], k in [1..2^7+1] | DivisorSigma(k, n) lt 2^7+1]))]
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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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