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A015871
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Numbers k such that phi(k + 5) | sigma(k) + 5.
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0
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1, 4, 9, 16, 18, 64, 81, 729, 4096, 59049, 125316, 262144, 16777216
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OFFSET
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1,2
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COMMENTS
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LINKS
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MATHEMATICA
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Select[Range[100000],
Divisible[DivisorSigma[1, #] + 5, EulerPhi[# + 5]] &] (* David Nacin, Feb 28 2012 *)
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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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