A238818 Number of Hamiltonian cycles on 2n X 2n grid with at least the symmetries of two reflections and 180-degree rotation.

1, 2, 6, 40, 488, 13782, 757626, 95835196, 24236840344, 13996574799274

Offset

1,2

Links

Table of n, a(n) for n=1..10.

Ed Wynn, Enumeration of nonisomorphic Hamiltonian cycles on square grid graphs, arXiv preprint arXiv:1402.0545 [math.CO], 2014.

Crossrefs

Cf. A003763.

Sequence in context: A081471 A133939 A045846 * A199574 A320489 A135755

Adjacent sequences: A238815 A238816 A238817 * A238819 A238820 A238821

Keyword

nonn,more

Author

N. J. A. Sloane, Mar 05 2014

Status

approved