A207985 Number of nX4 0..2 arrays avoiding the pattern z z+1 z horizontally and z z-1 z vertically.

69, 4761, 244325, 12271227, 622569385, 31638012071, 1607243845009, 81641053794111, 4147075467417469, 210658289444343157, 10700760566367351027, 543563676726218129663, 27611262828599058482901, 1402562262828848350945747

Offset: 1

Author

R. H. Hardin Feb 22 2012

Keywords

• nonn

Comments

Column 4 of A207989

Examples

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

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210