This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A055707 #16 Mar 03 2020 08:58:33
%S A055707 1,2,12,34,42,90,170,198,402,434,456,482,494,2046,4086,4518,7520,7605,
%T A055707 8622,9632,10924,28280,51570,51714,74124,77724,100172,139653,143136,
%U A055707 176760,294588,399980,471826,675356,690534,1358360,1577696,2089074,2121940,2136256
%N A055707 Numbers k such that k | sigma_13(k) - phi(k)^13.
%C A055707 sigma_13(k) is the sum of the 13th powers of the divisors of k (A013961).
%H A055707 Amiram Eldar, <a href="/A055707/b055707.txt">Table of n, a(n) for n = 1..100</a>
%t A055707 Do[If[Mod[DivisorSigma[13, n]-EulerPhi[n]^13, n]==0, Print[n]], {n, 1, 10^5}]
%o A055707 (PARI) isok(n) = !((sigma(n, 13) - eulerphi(n)^13) % n); \\ _Michel Marcus_, Mar 02 2014
%Y A055707 Cf. A000010, A013961.
%K A055707 nonn
%O A055707 1,2
%A A055707 _Robert G. Wilson v_, Jun 09 2000
%E A055707 Definition corrected and more terms from _Michel Marcus_, Mar 02 2014