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A110817
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Numbers k such that (1/k)*sigma(k+1) is an integer.
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1
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OFFSET
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1,2
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COMMENTS
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These are all the terms up to 10^8.
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LINKS
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EXAMPLE
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sigma(2+1)/2 = 2, so 2 is a term of the sequence.
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MATHEMATICA
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Select[Range[10^6], IntegerQ[DivisorSigma[1, # + 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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EXTENSIONS
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STATUS
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approved
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