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 A157416 #26 Mar 07 2021 18:51:43 %S A157416 0,0,0,4,8,12,24,32,42,54 %N A157416 Length of maximal uncrossed cycle of knight moves on n X n board. %C A157416 I had computed the values for n up to 8 long ago and reported them in a letter to the editor of the Journal of Recreational Mathematics 2 (1969), 155-157. The values for n=9 and n=10 are new, found using ZDDs. %C A157416 For best known results see link to Alex Chernov's site. - _Dmitry Kamenetsky_, Mar 02 2021 %D A157416 D. E. Knuth, Selected Papers on Fun and Games. CSLI, Stanford, CA, 2010. (CSLI Lecture Notes, vol. 192) %H A157416 Alex Chernov, <a href="http://ukt.alex-black.ru/">Uncrossed Knight's Tours</a>. %e A157416 Lengths of longest uncrossed knight cycles on all sufficiently small rectangular boards m X n, with 3 <=m <= n: %e A157416 ......0...0...4...6...6...6...6..10 %e A157416 ..........4...6...8..10..12..14..16 %e A157416 ..............8..12..14..18..20..22 %e A157416 .................12..18..22..24..28 %e A157416 .....................24..26..32..36 %e A157416 .........................32..36..42 %e A157416 .............................42..50 %e A157416 .................................54 %Y A157416 Cf. A003192. %K A157416 nonn,more,hard %O A157416 1,4 %A A157416 _Don Knuth_, Jun 24 2010 %E A157416 a(1)=a(2)=a(3)=0 prepended by _Max Alekseyev_, Jul 17 2011