

A140519


Number of "king tours" on an n X n board.


3




OFFSET

1,2


COMMENTS

Or, number of Hamiltonian cycles in the graph P_n X P_n.
If the direction of the tour is to be taken into account, the numbers for n > 1 must be multiplied by 2 (see A140521).
Computed using ZDDs (ZDD = "reduced, order, zerosuppressed binary decision diagram").


REFERENCES

D. E. Knuth, The Art of Computer Programming, Section 7.1.4, in preparation.


LINKS

Table of n, a(n) for n=1..8.
Index entries for sequences related to graphs, Hamiltonian


CROSSREFS

Cf. A001230, A140521.
Sequence in context: A080273 A096404 A111824 * A174506 A109216 A090478
Adjacent sequences: A140516 A140517 A140518 * A140520 A140521 A140522


KEYWORD

nonn,walk


AUTHOR

D. E. Knuth, Jul 26 2008


STATUS

approved



