A183443 Number of n X n binary arrays with every 1 having exactly two king-move neighbors equal to 1

1, 5, 18, 72, 2054, 53608, 1744887, 216103851, 39184763856, 11314547102638, 7873316318240100, 9711485486581483616, 21262647899259681841579

Offset

1,2

Comments

Diagonal of A183450

Links

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

Example

Some solutions for 5X5
..0..0..0..0..0....0..0..0..1..0....0..0..1..0..0....0..1..0..0..0
..1..0..0..0..0....0..1..1..0..1....0..1..0..1..0....1..1..0..1..0
..1..1..0..1..1....1..0..0..0..1....1..0..0..0..1....0..0..0..1..1
..0..0..0..0..1....1..0..0..0..1....1..0..0..0..1....1..1..0..0..0
..0..0..0..0..0....0..1..1..1..0....0..1..1..1..0....0..1..0..0..0

Crossrefs

Sequence in context: A302077 A322773 A145780 * A034551 A052926 A296123

Adjacent sequences: A183440 A183441 A183442 * A183444 A183445 A183446

Keyword

nonn

Author

R. H. Hardin Jan 04 2011

Status

approved