A208290 Number of 6 X n 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 1 1 0 vertically.

12, 144, 636, 3900, 21096, 119580, 665892, 3733080, 20874900, 116842500, 653759952, 3658440924, 20471559852, 114555114720, 641024680212, 3587040344820, 20072307438840, 112320368080068, 628520819264292

Offset: 1

Author

R. H. Hardin, Feb 25 2012

Keywords

• nonn

Comments

Row 6 of A208287.

Examples

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

Links

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

Crossrefs

Cf. A208287.

Formula

Empirical: a(n) = 4*a(n-1) + 11*a(n-2) - 10*a(n-3) - 10*a(n-4) + 6*a(n-5) + 2*a(n-6) - a(n-7).

Empirical g.f.: 12*x*(1 - x)*(1 + 9*x + 3*x^2 - 6*x^3 - x^4 + x^5) / (1 - 4*x - 11*x^2 + 10*x^3 + 10*x^4 - 6*x^5 - 2*x^6 + x^7). - Colin Barker, Jun 30 2018