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A110817
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Numbers n such that (1/n)sigma(n+1) is an integer.
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0
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OFFSET
| 1,2
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COMMENTS
| These are all the terms up to 10^8.
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EXAMPLE
| sigma(2+1)/2 = 2, so 2 is a term of the sequence.
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MATHEMATICA
| Select[Range[10^6], IntegerQ[DivisorSigma[1, # + 1]/# ] &]
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CROSSREFS
| Sequence in context: A197314 A064448 A173215 * A189428 A110860 A050995
Adjacent sequences: A110814 A110815 A110816 * A110818 A110819 A110820
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KEYWORD
| nonn
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AUTHOR
| Joseph L. Pe (joseph_l_pe(AT)hotmail.com), Sep 15 2005
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EXTENSIONS
| a(6) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Nov 15 2009
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