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A015797
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Numbers n such that phi(n) + 6 | sigma(n).
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1
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14, 20, 54, 56, 234, 286, 456, 686, 735, 980, 1176, 1224, 1470, 2000, 3296, 21645, 34632, 37496, 43290, 46620, 62336, 191616, 277808, 779568, 1124528, 4095712, 16726016, 17409376, 50251776, 149911936, 177383296, 12883623936, 42932880896, 295964664896
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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phi(14)+6 = 12, which divides sigma(14)=24, so 14 is in the sequence.
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MATHEMATICA
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Select[Range[100000],
Divisible[DivisorSigma[1, #], EulerPhi[#] + 6] &] (* David Nacin, Feb 28 2012 *)
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PROG
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(PARI) isok(n) = (sigma(n) % (eulerphi(n) + 6)) == 0; \\ Michel Marcus, Jul 15 2017
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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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