A207119 Number of nX4 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 0 1 and 0 1 1 vertically.

9, 81, 288, 1024, 2560, 6400, 13200, 27225, 49665, 90601, 151704, 254016, 399168, 627264, 938520, 1404225, 2020425, 2907025, 4051080, 5645376, 7660224, 10394176, 13789048, 18292729, 23801505, 30969225, 39622800, 50694400, 63909120, 80568576

Offset: 1

Author

R. H. Hardin Feb 15 2012

Keywords

• nonn

Comments

Column 4 of A207123

Examples

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

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +6*a(n-2) -14*a(n-3) -14*a(n-4) +42*a(n-5) +14*a(n-6) -70*a(n-7) +70*a(n-9) -14*a(n-10) -42*a(n-11) +14*a(n-12) +14*a(n-13) -6*a(n-14) -2*a(n-15) +a(n-16)