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 A055701 #15 Nov 19 2024 01:02:40
%S A055701 1,2,10,12,26,42,172,456,588,1326,3315,3635,6468,6720,12102,12922,
%T A055701 15288,17836,18810,21756,32984,36108,36603,40572,41748,72905,78120,
%U A055701 137004,195216,291060,295176,923212,978014,989604,1009800,1015768,1069712,1602692,1711024
%N A055701 Numbers k such that k | sigma_7(k) - phi(k)^7.
%C A055701 sigma_7(k) is the sum of the 7th powers of the divisors of k (A013955).
%H A055701 Amiram Eldar, <a href="/A055701/b055701.txt">Table of n, a(n) for n = 1..120</a>
%t A055701 Do[If[Mod[DivisorSigma[7, n]-EulerPhi[n]^7, n]==0, Print[n]], {n, 1, 10^5}]
%t A055701 Select[Range[2*10^6],Divisible[DivisorSigma[7,#]-EulerPhi[#]^7,#]&] (* _Harvey P. Dale_, Dec 02 2016 *)
%o A055701 (PARI) isok(n) = !((sigma(n, 7) - eulerphi(n)^7) % n); \\ _Michel Marcus_, Mar 02 2014
%Y A055701 Cf. A000010, A013955.
%K A055701 nonn
%O A055701 1,2
%A A055701 _Robert G. Wilson v_, Jun 09 2000
%E A055701 Definition corrected and more terms from _Michel Marcus_, Mar 02 2014