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 A158074 #17 Feb 16 2025 08:33:09 %S A158074 0,0,0,0,32,352,3072,30848,295456,2896832,28120096,273895232, %T A158074 2664515712,25931157504,252338724352,2455552258304,23895692937216, %U A158074 232533011307776,2262837745837568,22020130538878208,214282979451801088,2085233793265765376,20291876152214982656 %N A158074 Number of (directed) Hamiltonian cycles on a 3 X (2n) knight's tour graph. %H A158074 Seiichi Manyama, <a href="/A158074/b158074.txt">Table of n, a(n) for n = 1..1000</a> %H A158074 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/KnightsTour.html">Knight's Tour</a> %F A158074 a(n) = 2*A070030(n). %F A158074 a(n) = 6*a(n-1) + 64*a(n-2) - 200*a(n-3) - 1000*a(n-4) + 3016*a(n-5) + 3488*a(n-6) - 24256*a(n-7) + 23776*a(n-8) + 104168*a(n-9) - 203408*a(n-10) - 184704*a(n-11) + 443392*a(n-12) + 14336*a(n-13) - 151296*a(n-14) + 145920*a(n-15) - 263424*a(n-16) + 317440*a(n-17) + 36864*a(n-18) - 966656*a(n-19) + 573440*a(n-20) + 131072*a(n-21), for n>=23. (See A070030) - _Seiichi Manyama_, Dec 16 2016 %Y A158074 Cf. A070030 for details and references. %K A158074 nonn %O A158074 1,5 %A A158074 _Eric W. Weisstein_, Mar 13 2009 %E A158074 Extended by _Eric W. Weisstein_, Mar 18 2009