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 A039818 #14 May 07 2019 07:02:27 %S A039818 4409,67307,86573,111857,198349,259507 %N A039818 Erroneous version of A158124. %K A039818 dead %O A039818 0,1