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 A131204 #34 Feb 12 2023 15:19:55 %S A131204 17,97,113,193,241,257,337,353,401,433,449,577,593,641,673,769,881, %T A131204 929,977,1009,1153,1201,1217,1249,1297,1361,1409,1489,1553,1601,1697, %U A131204 1777,1873,1889,2017,2081,2113,2129,2161,2273,2417,2593,2609,2657,2689,2753,2801 %N A131204 Duplicate of A094407. %K A131204 dead %O A131204 1,1