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 A048238 #5 Nov 10 2007 03:00:00 %S A048238 1,2,4,8,14,27,47,86,149,261,444,760,1269,2119,3486,5711,9247,14906 %N A048238 Duplicate of A048140. %K A048238 dead %O A048238 1,2