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 A303866 #7 May 03 2018 14:55:45 %S A303866 1,3,36,960,35956,1588192,77381016,4031052368,220584971892, %T A303866 12535415236272,734006917110352,44036846006084336,2695712407044476920, %U A303866 167837690527630068192,10601944003900014217704,678116169233319969588160,43848248800067454244195956,2862607888444933662236506240 %N A303866 Number of noncrossing path sets on 4*n nodes up to rotation with each path having exactly 4 nodes. %H A303866 Andrew Howroyd, <a href="/A303866/b303866.txt">Table of n, a(n) for n = 0..200</a> %Y A303866 Column 4 of A303864. %Y A303866 Cf. A303865, A303867. %K A303866 nonn %O A303866 0,2 %A A303866 _Andrew Howroyd_, May 01 2018