A207217 Number of nX4 0..2 arrays avoiding the pattern z z+1 z in any row or column.

69, 4761, 247163, 12584703, 647820815, 33403462497, 1721695415743, 88730578258613, 4572950799187243, 235680064764200747, 12146435820476346225, 626000438753879535467, 32262680221309448337639, 1662747377281516450070519

Offset: 1

Author

R. H. Hardin Feb 16 2012

Keywords

• nonn

Comments

Column 4 of A207221

Examples

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

Links

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