A222200 Number of Hamiltonian cycles on n X n+1 square grid of points.

1, 2, 14, 154, 5320, 301384, 49483138, 13916993782, 10754797724124, 14746957510647992, 53540340738182687296, 354282765498796010420944, 6040964455632840415885507728, 191678405883294971709423926242394, 15351055042300622367048024911122943712

Offset: 2

Author

N. J. A. Sloane, Feb 14 2013

Keywords

• nonn

Links

• Peter Tittmann, Enumeration in graphs: counting Hamiltonian cycles [Broken link?]
• Peter Tittman, Illustration of a(4) = 14 [Taken from preceding link]
• Peter Tittmann, Enumeration in graphs: counting Hamiltonian cycles [Backup copy of top page only, on the Internet Archive]
• Index entries for sequences related to graphs, Hamiltonian

Crossrefs

Cf. A003763, A321172.

Formula

a(n) = A321172(n,n+1) = A321172(n+1,n). - Robert FERREOL, Apr 01 2019

Extensions

a(16) from Huaide Cheng, Jul 02 2025