A070272 Numbers n such that reverse(n) = phi(n) + sigma(n).
275, 295, 2995, 299995, 2999995, 278736495, 299999995, 299999999995
Offset: 1
Examples
Reverse(275) = 572 = 200 + 372 = phi(275) + sigma(275).
Programs
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Mathematica
Select[Range[10^6], FromDigits[Reverse[IntegerDigits[ # ]]] == EulerPhi[ # ] + DivisorSigma[1, # ] &]
Extensions
One more term from Farideh Firoozbakht, Jan 11 2005
More terms from Farideh Firoozbakht, Jan 23 2005
a(8) from Giovanni Resta, Nov 03 2012
Comments