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 A005781 #8 Dec 10 2024 06:12:21 %S A005781 2,5,6,8,9,11 %N A005781 Erroneous version of A273867. %K A005781 dead %O A005781 1,1