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 A343227 #9 May 24 2021 00:45:26 %S A343227 1,1,1,7,1,12,1,3,13,18,1,1,1,24,24,31,1,1,1,21,32,36,1,15,31,42,20, %T A343227 14,1,72,1,9,48,54,48,91,1,60,56,5,1,96,1,21,13,72,1,31,19,93,72,49,1, %U A343227 8,72,30,80,90,1,21,1,96,52,127,84,144,1,9,96,48,1,65,1,114,62,35,96,168,1,93,121,126,1,14,108 %N A343227 a(n) = sigma(n) / gcd(sigma(n), n+A003415(n)), where A003415 is the arithmetic derivative, and sigma is the sum of divisors of n. %H A343227 Antti Karttunen, <a href="/A343227/b343227.txt">Table of n, a(n) for n = 1..16384</a> %H A343227 Antti Karttunen, <a href="/A343227/a343227.txt">Data supplement: n, a(n) computed for n = 1..65537</a> %H A343227 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a> %F A343227 a(n) = A000203(n) / A343226(n) = A000203(n) / gcd(A000203(n), n+A003415(n)) %Y A343227 Cf. A000203, A003415, A129283, A343226. %K A343227 nonn %O A343227 1,4 %A A343227 _Antti Karttunen_, Apr 15 2021