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 A058869 #4 Sep 29 2006 03:00:00 %S A058869 5,53,211,20201,16787,69623,255803,247141,3565979,6314447,4911311 %N A058869 Duplicate of A054342. %K A058869 dead %O A058869 1,1