A308129 Number of (undirected) Hamiltonian paths on the n X n king graph.

1, 12, 392, 171592, 364618672, 6544911081900, 829555065360355292, 817534730458899350635436, 6154392250018061759082363305112, 360916610325065945171647827293872547848, 165298493343313203241690299664254975948394404072

Offset: 1

Author

Eric W. Weisstein, May 14 2019

Keywords

• nonn
• hard

Links

• Eric Weisstein's World of Mathematics, Hamiltonian Path
• Eric Weisstein's World of Mathematics, King Graph

Crossrefs

Main diagonal of A350729.

Cf. A140518, A158651, A272445, A288033.

Formula

a(n) = A158651(n)/2 for n > 1.

Extensions

a(1) corrected by Andrew Howroyd, Jan 16 2022