OFFSET
1,4
COMMENTS
1. Jelliss computes the number of tour diagrams (which is equal to half the number of tours). 2. Sequence A079137 computes the number of tour DIAGRAMS for a 4 X k board (again, equal to half the number of tours). 3. Kraitchik (1942) incorrectly reports 376 tour diagrams for the 3 X 8 case; the correct number is 396 (i.e., 792 tours) [cf. Rose, Jelliss].
REFERENCES
Kraitchik, M., Mathematical Recreations. New York: W. W. Norton, pp. 264-5, 1942.
LINKS
Seiichi Manyama, Table of n, a(n) for n = 1..1861
G. Jelliss, Open Knight's Tours of Three-Rank Boards
Seiichi Manyama calculated a(14)-a(21) by yoh2's code
C. Rose, The Distribution of the Knight.
Eric Weisstein's World of Mathematics, Hamiltonian Path
Eric Weisstein's World of Mathematics, Knight Graph
FORMULA
a(n) = 2 * A169696(n). - Andrew Howroyd, Jul 01 2017
MATHEMATICA
Mathematica notebook available at: http://www.tri.org.au/knightframe.html
CROSSREFS
KEYWORD
nonn
AUTHOR
Colin Rose, May 11 2006
EXTENSIONS
a(13) from Eric W. Weisstein, Mar 13 2009
a(14)-a(21) from Seiichi Manyama, Apr 25 2016
a(22)-a(28) from Andrew Howroyd, Jul 01 2017
STATUS
approved