A318418 Number of nXn 0..1 arrays with every element unequal to 0, 2, 3 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

1, 2, 2, 18, 129, 783, 11802, 236755, 5897333, 182618347, 7672658026, 436957466532

Offset

1,2

Comments

Diagonal of A318423.

Links

Table of n, a(n) for n=1..12.

Example

Some solutions for n=5
..0..1..0..0..1. .0..1..1..0..0. .0..0..0..1..0. .0..0..1..0..0
..1..0..1..0..0. .1..0..1..0..0. .0..0..1..1..1. .0..1..1..1..1
..0..0..0..1..0. .1..1..1..1..1. .0..1..1..0..0. .1..1..0..1..0
..1..1..0..0..1. .0..0..1..1..0. .1..1..0..0..1. .0..1..1..0..0
..1..1..0..1..0. .0..0..1..0..1. .0..1..0..1..1. .0..1..0..0..0

Crossrefs

Cf. A318423.

Sequence in context: A173785 A264715 A294341 * A184317 A141084 A172194

Adjacent sequences: A318415 A318416 A318417 * A318419 A318420 A318421

Keyword

nonn

Author

R. H. Hardin, Aug 26 2018

Status

approved