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 A072615 #4 May 11 2007 03:00:00 %S A072615 0,3,16,81,392,1815,8112,35301,150544,632043,2620880,10759353 %N A072615 Duplicate of A020871. %K A072615 dead %O A072615 0,2