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%I #22 Nov 19 2024 17:32:31
%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 k such that k | sigma_11(k) - phi(k)^11.
%C sigma_11(k) is the sum of the 11th powers of the divisors of k (A013959).
%H Amiram Eldar, <a href="/A055705/b055705.txt">Table of n, a(n) for n = 1..124</a>
%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, A013959.
%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