A228500 Number of n X n binary arrays with top left value 1 and no two ones adjacent horizontally, vertically, diagonally or antidiagonally.

1, 1, 12, 87, 2002, 59839, 3862849, 405580157, 81304395949, 28446567810005, 18268841726936268, 20937720031330292269, 43502129718103134992611, 162426195975365708781849519, 1095156092719874995442597502324

Offset: 1

Author

R. H. Hardin Aug 23 2013

Keywords

• nonn

Comments

Diagonal of A228506

Examples

			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..0..0..1
..1..0..0..1....0..1..0..1....0..0..0..0....0..0..1..0....0..0..0..0
..0..0..0..0....0..0..0..0....0..1..0..0....1..0..0..0....0..0..0..1
		

Links

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