A281073 Number of n X n 0..1 arrays with no element equal to more than two of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.

0, 0, 55, 958, 10954, 89042, 566178, 3035844, 14551996, 65113158, 280515214, 1187820788, 5004343732

Offset

1,3

Comments

Diagonal of A281080.

Links

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

Example

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

Crossrefs

Cf. A281080.

Sequence in context: A358634 A241634 A008402 * A329753 A203872 A297753

Adjacent sequences: A281070 A281071 A281072 * A281074 A281075 A281076

Keyword

nonn

Author

R. H. Hardin, Jan 14 2017

Status

approved