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A066152
Numbers k such that EulerPhi(k) = sigma(k+1) - sigma(k).
1
2, 459, 17835, 34089, 55419, 61183, 180785, 194139, 248501, 385671, 907323, 988455, 1374735, 1407413, 1408253, 1452135, 1749087, 2451727, 3026705, 3263585, 3831487, 6541695, 7633989, 9336785, 12750833, 16543433, 16573963, 21248201
OFFSET
1,1
LINKS
EXAMPLE
EulerPhi(459) = 288 = 1008 - 720 = sigma(460) - sigma(459). [corrected by Harry J. Smith, Feb 03 2010]
MATHEMATICA
Select [Range[1, 10^6], EulerPhi[ # ] == DivisorSigma[1, # + 1] - DivisorSigma[1, # ] & ]
PROG
(PARI) { n=0; for (m=1, 10^9, if (eulerphi(m) == sigma(m + 1) - sigma(m), write("b066152.txt", n++, " ", m); if (n==70, return)) ) } \\ Harry J. Smith, Feb 03 2010
CROSSREFS
Sequence in context: A012734 A363699 A099686 * A112862 A094484 A062620
KEYWORD
nonn
AUTHOR
Joseph L. Pe, Dec 13 2001
EXTENSIONS
More terms from Robert G. Wilson v, Dec 27 2001
a(25)-a(28) from Harry J. Smith, Feb 03 2010
STATUS
approved