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A066154
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Numbers k such that EulerPhi(k) = sigma(k) - sigma(k-1).
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1
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574, 3496, 148708, 380276, 604504, 703402, 1223194, 1961218, 2375854, 5153085, 13182476, 15089116, 15624820, 18503524, 19402515, 22352968, 27366118, 41377798, 42917332, 51062116, 58911736, 60113914, 74657636, 75018856
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OFFSET
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1,1
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LINKS
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EXAMPLE
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EulerPhi(574) = 240 = 1008 - 768 = sigma(574) - sigma(573).
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MATHEMATICA
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Select [Range[1, 10^7], EulerPhi[ # ] == DivisorSigma[1, # ] - DivisorSigma[1, # - 1] & ]
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PROG
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(PARI) { n=0; for (m=2, 10^9, if (eulerphi(m) == sigma(m) - sigma(m - 1), write("b066154.txt", n++, " ", m); if (n==100, return)) ) } \\ Harry J. Smith, Feb 03 2010
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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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