A207215 Number of n X n 0..2 arrays avoiding the pattern z z+1 z in any row or column.

3, 81, 12534, 12584703, 86510224720, 4019515127529418, 1256433426475190769775, 2643803004141585682944365943

Offset: 1

Author

R. H. Hardin Feb 16 2012

Keywords

• nonn

Comments

Diagonal of A207221

Examples

			Some solutions for n=4
..2..0..2..1....2..1..0..2....2..0..0..0....2..0..1..1....0..2..0..1
..1..1..1..0....1..1..1..2....0..1..1..0....2..1..0..1....2..0..1..1
..0..1..2..2....1..1..2..2....0..1..1..2....1..2..2..2....0..2..1..1
..0..0..0..2....1..1..0..1....2..2..0..1....1..0..0..0....2..0..0..1