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%I #10 Dec 02 2016 10:22:15
%S 1,2,10,12,26,42,172,456,588,1326,3315,3635,6468,6720,12102,12922,
%T 15288,17836,18810,21756,32984,36108,36603,40572,41748,72905,78120,
%U 137004,195216,291060,295176,923212,978014,989604,1009800,1015768,1069712,1602692,1711024
%N Numbers n such that n | Sigma_7(n) - Phi(n)^7.
%C sigma_7(n) is the sum of the 7th powers of the divisors of n (A013955).
%t Do[If[Mod[DivisorSigma[7, n]-EulerPhi[n]^7, n]==0, Print[n]], {n, 1, 10^5}]
%t Select[Range[2*10^6],Divisible[DivisorSigma[7,#]-EulerPhi[#]^7,#]&] (* _Harvey P. Dale_, Dec 02 2016 *)
%o (PARI) isok(n) = !((sigma(n, 7) - eulerphi(n)^7) % n); \\ _Michel Marcus_, Mar 02 2014
%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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