A296535 Number of n X n 0..1 arrays with each 1 horizontally, vertically or antidiagonally adjacent to 2 or 4 neighboring 1's.

1, 3, 16, 126, 2104, 78660, 5705431, 820373528, 239372827502, 141301759543525, 168080053760638246, 403684916425998696873

Offset

1,2

Comments

Diagonal of A296541.

Links

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

Example

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

Crossrefs

Cf. A296541.

Sequence in context: A247591 A188805 A214645 * A088358 A082161 A264636

Adjacent sequences: A296532 A296533 A296534 * A296536 A296537 A296538

Keyword

nonn

Author

R. H. Hardin, Dec 15 2017

Status

approved