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 A060135 #10 Jun 12 2021 23:34:57
%S A060135 1,2,1,2,1,3,1,2,3,2,1,2,1,2,3,2,1,3,1,2,1,2,1
%N A060135 Sequence of adjacent transpositions (a[n] a[n]+1), which, when starting from the identity permutation and applied successively, produce a Hamiltonian circuit through all permutations of S_4, in such a way that S_{n-1} is always traversed before the rest of S_n. Furthermore, each subsequence from the first to the (n!-1)-th term is palindromic.
%C A060135 This is lexicographically the ninth of all such Hamiltonian paths through S4.
%C A060135 I will try to extend this in some elegant fashion through all S_inf so that the same criteria will hold. There are 466 ways to extend this to S5.
%H A060135 A. Karttunen, <a href="http://www.iki.fi/~kartturi/matikka/permgraf/troctahe.htm">Truncated octahedron</a>
%H A060135 <a href="/index/Be#bell_ringing">Index entries for sequences related to bell ringing</a>
%F A060135 [seq(sol9seq(n), n=1..23)];
%p A060135 sol9seq := n -> (`if`((n < 13),adj_tp_seq(n), sol9seq(24-n)));
%Y A060135 Cf. A057112.
%K A060135 nonn
%O A060135 0,2
%A A060135 _Antti Karttunen_, Mar 02 2001