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%I #16 Mar 03 2020 08:58:33
%S 1,2,12,34,42,90,170,198,402,434,456,482,494,2046,4086,4518,7520,7605,
%T 8622,9632,10924,28280,51570,51714,74124,77724,100172,139653,143136,
%U 176760,294588,399980,471826,675356,690534,1358360,1577696,2089074,2121940,2136256
%N Numbers k such that k | sigma_13(k) - phi(k)^13.
%C sigma_13(k) is the sum of the 13th powers of the divisors of k (A013961).
%H Amiram Eldar, <a href="/A055707/b055707.txt">Table of n, a(n) for n = 1..100</a>
%t Do[If[Mod[DivisorSigma[13, n]-EulerPhi[n]^13, n]==0, Print[n]], {n, 1, 10^5}]
%o (PARI) isok(n) = !((sigma(n, 13) - eulerphi(n)^13) % n); \\ _Michel Marcus_, Mar 02 2014
%Y Cf. A000010, A013961.
%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