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 A039620 #5 Jun 29 2008 03:00:00 %S A039620 1,1,1,-1,3,1,2,-1,6,1,-6,0,4,5,10,1,24,4,-15,25,15,1,-120,-28,49,-35 %N A039620 Erroneous version of A008296. %K A039620 dead %O A039620 1,5