A295199 Number of n X n 0..1 arrays with each 1 horizontally or vertically adjacent to 2 or 4 1's.

1, 2, 8, 42, 438, 8241, 279663, 17574795, 2023191364, 425872679440, 164093026377725, 115549694765467808, 148496731427890025827

Offset

1,2

Comments

Diagonal of A295205.

Links

Table of n, a(n) for n=1..13.

Example

Some solutions for n=6
..0..0..0..0..0..0. .1..1..0..1..1..1. .0..1..1..1..1..1. .0..1..1..1..0..0
..1..1..1..1..0..0. .1..1..1..1..0..1. .0..1..0..0..0..1. .0..1..0..1..0..0
..1..0..0..1..1..0. .0..1..0..0..0..1. .1..1..0..1..1..1. .1..1..0..1..1..0
..1..0..0..0..1..0. .0..1..1..0..0..1. .1..0..1..1..0..0. .1..0..0..0..1..1
..1..1..1..1..1..1. .0..0..1..1..1..1. .1..1..1..0..0..0. .1..1..1..1..0..1
..0..0..0..0..1..1. .0..0..0..0..0..0. .0..0..0..0..0..0. .0..0..0..1..1..1

Crossrefs

Cf. A295205.

Sequence in context: A191994 A153524 A153552 * A191479 A197935 A267619

Adjacent sequences: A295196 A295197 A295198 * A295200 A295201 A295202

Keyword

nonn

Author

R. H. Hardin, Nov 16 2017

Status

approved