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 A000858 #5 May 11 2007 03:00:00 %S A000858 0,1,4,31,293,3326,44189,673471,11588884,222304897,4704612119 %N A000858 Duplicate of A003436. %K A000858 dead %O A000858 1,3