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 A269510 #20 May 23 2019 08:26:16 %S A269510 2,8,8,18,18,32,32,50,50 %N A269510 Duplicate of A093907. %K A269510 dead %O A269510 1,1