A185827 Half the number of n X n binary arrays with every element equal to exactly one or two of its horizontal and vertical neighbors

0, 3, 30, 514, 15782, 923808, 91052720, 17200095426, 5976334149476, 3829861209246738

Offset

1,2

Comments

Diagonal of A185835

Links

Table of n, a(n) for n=1..10.

Example

Some solutions for 4X4 with a(1,1)=0
..0..0..1..1....0..0..1..1....0..0..0..1....0..1..1..1....0..0..1..1
..1..1..0..1....0..1..0..1....1..1..0..1....0..1..0..0....0..1..0..0
..0..0..0..1....0..1..0..1....0..1..0..1....0..1..1..0....1..1..0..1
..0..1..1..1....0..1..0..0....0..0..1..1....0..0..1..0....0..0..1..1

Crossrefs

Sequence in context: A366002 A338278 A144739 * A366009 A370910 A080527

Adjacent sequences: A185824 A185825 A185826 * A185828 A185829 A185830

Keyword

nonn

Author

R. H. Hardin Feb 05 2011

Status

approved