A208252 Number of n X n 0..2 arrays with new values 0..2 introduced in row major order and no element equal to more than one of its immediate leftward or upward neighbors.

1, 12, 2040, 2445264, 20662697664, 1230875651548608, 516901401841519506624, 1530268623239822606574667872, 31936997040921403605588139690977984, 4698799611233642481043318409392291549604736

Offset: 1

Author

R. H. Hardin Feb 24 2012

Keywords

• nonn

Comments

Diagonal of A208258

Examples

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

Links

• R. H. Hardin, Table of n, a(n) for n = 1..13