OFFSET
1,2
LINKS
Oliver R. Bellwood, Table of n, a(n) for n = 1..18 (terms 1..17 from Jesper L. Jacobsen)
J. L. Jacobsen, Exact enumeration of Hamiltonian circuits, walks and chains in two and three dimensions, J. Phys. A: Math. Theor. 40 (2007) 14667-14678.
J.-M. Mayer, C. Guez and J. Dayantis, Exact computer enumeration of the number of Hamiltonian paths in small square plane lattices, Physical Review B, Vol. 42 Number 1, 1990.
Eric Weisstein's World of Mathematics, Grid Graph
Eric Weisstein's World of Mathematics, Hamiltonian Path
FORMULA
a(n) = A096969(n) / 2 for n > 1.
EXAMPLE
From Robert FERREOL, Apr 03 2019: (Start)
a(3) = 20:
there are 4 paths similar to
+ - + - +
|
+ - + - +
|
+ - + - +
8 paths similar to
+ - + - +
| |
+ + - +
| |
+ + - +
and 8 paths similar to
+ - + - +
| |
+ + +
| | |
+ + - +
(End)
CROSSREFS
KEYWORD
nonn,walk
AUTHOR
David Bevan, Jul 19 2006
EXTENSIONS
More terms from Jesper L. Jacobsen (jesper.jacobsen(AT)u-psud.fr), Dec 12 2007
STATUS
approved
