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 A078674 #5 Mar 30 2012 16:49:37 %S A078674 1,3,50,2122,155712,17441962 %N A078674 Number of ways to lace a shoe that has n pairs of eyelets, assuming the lacing satisfies certain conditions. %C A078674 The lace must follow a Hamiltonian path through the 2n eyelets and cannot pass in order though three adjacent eyelets that are in a line. %C A078674 The lace is "undirected": reversing the order of eyelets along the path does not count as a different solution (cf. A078629). %H A078674 <a href="/index/La#lacings">Index entries for sequences related to shoe lacings</a> %Y A078674 Apart from initial term, A078629/2. %K A078674 nonn %O A078674 1,2 %A A078674 _N. J. A. Sloane_, Dec 16 2002