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 A374170 #13 Jul 02 2024 02:13:47 %S A374170 20,20,6050,7203 %N A374170 a(n) is the least nonsquare k such that sigma_n(k) divides sigma_2n(k). %C A374170 a(1) = A227771(1); a(2) = A046871(5). %C A374170 a(5) > 10^9 if it exists. %C A374170 a(6) = 17328, a(7) = 50, a(13) = 761378. %o A374170 (PARI) a(n) = my(k=1, f=factor(k)); while (issquare(k) || (sigma(f, 2*n) % sigma(f, n)), f=factor(k++)); k; \\ _Michel Marcus_, Jun 30 2024 %Y A374170 Cf. A020487, A227771, A046871. %K A374170 nonn,more %O A374170 1,1 %A A374170 _Mohammed Yaseen_, Jun 30 2024