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A015800
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Numbers k such that phi(k) + 9 | sigma(k).
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1
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26, 312, 828, 2475, 2520, 4950, 7412, 7942, 10464, 14454, 30952, 89262, 1029632, 3116544, 17721152, 56889152, 538655552, 804839424, 9287924224, 206150959104, 698155922432
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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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MATHEMATICA
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Cases[Range[100000],
x_ /; Divisible[DivisorSigma[1, x], EulerPhi[x] + 9] == True] (* David Nacin, Feb 28 2012 *)
Select[Range[1000000], Divisible[DivisorSigma[1, #], EulerPhi[#]+9]&] (* Harvey P. Dale, May 24 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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