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 A089220 #3 Jun 29 2008 03:00:00 %S A089220 642427,1058861,3431903,4176587,4560121,4721047,5072269,5145403 %N A089220 Duplicate of A052243. %K A089220 dead %O A089220 1,1