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 A048897 #5 Jan 09 2009 03:00:00 %S A048897 1,5,1,45,15,1,585,255,30,1,9945,5175,825,50,1,208845,123795,24150 %N A048897 Duplicate of A049029. %K A048897 dead %O A048897 1,2