A222203 Number of ways to cover the n X n+1 grid graph by vertex disjoint cycles.

1, 3, 54, 1140, 99051, 13049563, 6044482889, 4738211572702, 11986520595161863, 54755153078468134960, 764291947227525464744293, 20119942924108379011391597989, 1558052539448513320447263528275071, 234788223520702255614480389250160811898, 101199388044301804167035198499446336399419451, 86918369741985767628242106496018767545685968221295

Offset

2,2

Links

Andrew Howroyd, Table of n, a(n) for n = 2..24

Peter Tittmann, Enumeration in graphs: counting Hamiltonian cycles [Archived link]

Robert Israel, The 54 solutions for n=4

Crossrefs

Cf. A222202, A222204.

Sequence in context: A065102 A223926 A003776 * A224051 A355365 A376282

Adjacent sequences: A222200 A222201 A222202 * A222204 A222205 A222206

Keyword

nonn

Author

N. J. A. Sloane, Feb 14 2013

Status

approved