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 A107683 #2 Apr 30 2014 01:29:21 %S A107683 1,1,3,11,35,114,407,1486,5414,19923,74230,278462,1049318,3972395, %T A107683 15101658,57607431,220391316,845366406,3250192681,12521965697 %N A107683 Number of perfect Skolem sets. %H A107683 G. Nordh, <a href="http://arXiv.org/abs/math.NT/0506155">Perfect Skolem sequences</a> %Y A107683 Cf. A004075, A060963, A099152. %K A107683 nonn %O A107683 1,3 %A A107683 _Ralf Stephan_, Jun 10 2005