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 A174706 #21 Dec 23 2024 14:53:42
%S A174706 1,0,0,0,0,2,14,12,0,0,0,0,30,104,112,48,40,48,112,400,964,1276,1202,
%T A174706 1280,1714,3004,6120,11472,16730,20884,26308,36676,57570,96642,158864,
%U A174706 237592,330064,453476,647862,975210,1515766,2345634,3505078,5064148,7241688
%N A174706 The number of permutations p of {1,...,n} such that |p(i)-p(i+1)| is in {3,4} for all i from 1 to n-1.
%C A174706 For n>1, a(n)/2 is the number of Hamiltonian paths on the graph with vertex set {1,...,n} where i is adjacent to j iff |i-j| is in {3,4}.
%H A174706 Andrew Howroyd, <a href="/A174706/b174706.txt">Table of n, a(n) for n = 1..500</a>
%H A174706 W. Edwin Clark, "<a href="https://web.archive.org/web/*/http://list.seqfan.eu/oldermail/seqfan/2010-March/004193.html">permutations p in S_n such that m <= |p(i)-p(i+1)| <= M for i from 1 to n-1</a>", SeqFan Discussion, Mar 2010.
%Y A174706 Cf. A003274, A174700, A174701, A174702, A174703, A174704, A174705, A174707, A174708, A185030, A216837.
%K A174706 nonn
%O A174706 1,6
%A A174706 _W. Edwin Clark_, Mar 27 2010
%E A174706 a(28)-a(38) from _Robert Gerbicz_, Nov 27 2010
%E A174706 a(39)-a(45) from _Andrew Howroyd_, Apr 05 2016