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A001230
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Number of undirected closed knight's tours on a 2n X 2n chessboard.
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12
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OFFSET
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1,3
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COMMENTS
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No closed tour exists on an m X m board if m is odd.
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REFERENCES
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Brendan McKay, personal communication, Feb 03, 1997.
W. W. Rouse Ball, Mathematical Recreations and Essays (various editions), Chap. 6.
I. Wegener, Branching Programs and Binary Decision Diagrams, SIAM, Philadelphia, 2000; see p. 369.
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LINKS
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MATHEMATICA
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Table[Length[FindHamiltonianCycle[KnightTourGraph[2 n, 2 n], All]], {n, 3}]
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CROSSREFS
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KEYWORD
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nonn,hard,more,nice
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AUTHOR
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EXTENSIONS
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Loebbing and Wegener incorrectly gave 33439123484294 for the 8 X 8 board. The value given here is due to Brendan McKay and agrees with that given by Wegener in his book.
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STATUS
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approved
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