A265441 Number of nX2 0..n+2-2 arrays with upper left zero and lower right n+2-2 and each element differing from its horizontal and vertical neighbors by one or two.

1, 1, 2, 53, 455, 2218, 9702, 59956, 444998, 2915881, 16984838, 100144150, 638465320, 4169033187, 26450244798, 164385366814, 1031338919194, 6581317747223, 42129509368387, 268046060285802, 1701181410512570

Offset

1,3

Comments

Column 2 of A265447.

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Example

Some solutions for n=4
..0..2....0..2....0..2....0..1....0..2....0..1....0..2....0..2....0..2....0..2
..2..3....2..4....2..1....2..3....2..1....1..2....2..1....2..0....2..1....2..0
..4..2....1..2....1..3....0..2....0..2....2..3....4..3....4..2....1..2....0..2
..3..4....3..4....2..4....2..4....2..4....3..4....3..4....3..4....2..4....2..4

Crossrefs

Cf. A265447.

Sequence in context: A119112 A356488 A109791 * A354406 A119777 A176943

Adjacent sequences: A265438 A265439 A265440 * A265442 A265443 A265444

Keyword

nonn

Author

R. H. Hardin, Dec 09 2015

Status

approved