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 A087257 #3 May 11 2007 03:00:00 %S A087257 1,2,4,8,16,20,24,32,40,48,52,56,64,68,72,80,84,88,96,100,104,112,116 %N A087257 Duplicate of A033496. %K A087257 dead %O A087257 0,2