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 A243080 #12 Apr 28 2025 12:26:57 %S A243080 1,1,2,5,9,20,13,12,5,3,1,1 %N A243080 Duplicate of A030137. %K A243080 dead %O A243080 1,3