A228654 Number of n X n binary arrays with top left value 1 and no two ones adjacent horizontally, diagonally or antidiagonally.

1, 2, 34, 416, 24109, 1482892, 337258048, 99770848656, 92600434253746, 128571982215641568, 497887042842429868023, 3189515020018986830642404, 52334113476786453501159739264, 1527284319716267796002249895255726

Offset

1,2

Comments

Diagonal of A228660

Links

R. H. Hardin, Table of n, a(n) for n = 1..29

Example

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

Crossrefs

Sequence in context: A224294 A092408 A180764 * A005261 A104898 A218432

Adjacent sequences: A228651 A228652 A228653 * A228655 A228656 A228657

Keyword

nonn

Author

R. H. Hardin Aug 29 2013

Status

approved