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A140521
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Number of directed "king tours" on an n X n board.
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4
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OFFSET
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1,2
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COMMENTS
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Or, number of directed Hamiltonian cycles in the graph P_n X P_n.
If the direction of the tour is not taken into account, the numbers for n > 1 must be halved (see A140519).
Computed using ZDDs (ZDD = "reduced, order, zero-suppressed binary decision diagram").
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REFERENCES
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Donald E. Knuth, The Art of Computer Programming, Vol. 4, fascicle 1, section 7.1.4, p. 117, Addison-Wesley, 2009.
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LINKS
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CROSSREFS
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KEYWORD
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nonn,walk
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AUTHOR
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STATUS
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approved
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