A228476 Number of n X n binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or antidiagonally.

1, 2, 14, 172, 4354, 211588, 20185842, 3737615288, 1349721589622, 948593164919044, 1298594593323021084, 3461591189556243601228, 17969903126848842785918376, 181660279488635404176787338286

Offset

1,2

Comments

Diagonal of A228482

Links

R. H. Hardin, Table of n, a(n) for n = 1..27

Example

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

Crossrefs

Sequence in context: A235369 A380040 A351274 * A308449 A233224 A167014

Adjacent sequences: A228473 A228474 A228475 * A228477 A228478 A228479

Keyword

nonn

Author

R. H. Hardin Aug 22 2013

Status

approved