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 A055705 Numbers n such that n | Sigma_11(n) - Phi(n)^11. 0

%I

%S 1,2,10,12,82,168,952,1716,2732,2970,5627,8185,11400,12871,20104,

%T 20368,23526,25749,70176,82920,111194,117151,119160,128790,134670,

%U 143136,185140,193020,208352,240408,247995,251856,291368,354588,565768,592006,642600,783315

%N Numbers n such that n | Sigma_11(n) - Phi(n)^11.

%C sigma_11(n) is the sum of the 11th powers of the divisors of n (A013959).

%t Do[If[Mod[DivisorSigma[11, n]-EulerPhi[n]^11, n]==0, Print[n]], {n, 10^5}]

%t Select[Range[800000],Divisible[DivisorSigma[11,#]-EulerPhi[#]^11,#]&] (* _Harvey P. Dale_, Apr 15 2018 *)

%o (PARI) isok(n) = !((sigma(n, 11) - eulerphi(n)^11) % n); \\ _Michel Marcus_, Mar 02 2014

%Y Cf. A000010.

%K nonn

%O 1,2

%A _Robert G. Wilson v_, Jun 09 2000

%E Definition corrected and more terms from _Michel Marcus_, Mar 02 2014

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Last modified December 6 08:53 EST 2019. Contains 329788 sequences. (Running on oeis4.)