A207167 Number of n X 6 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 0 1 and 1 0 1 vertically.

19, 361, 1482, 3952, 8455, 15789, 26866, 42712, 64467, 93385, 130834, 178296, 237367, 309757, 397290, 501904, 625651, 770697, 939322, 1133920, 1356999, 1611181, 1899202, 2223912, 2588275, 2995369, 3448386, 3950632, 4505527, 5116605

Offset: 1

Author

R. H. Hardin, Feb 15 2012

Keywords

• nonn

Comments

Column 6 of A207169.

Examples

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

Links

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

Crossrefs

Cf. A207169.

Formula

Empirical: a(n) = (19/4)*n^4 + (95/2)*n^3 - (57/4)*n^2 - 19*n.

Conjectures from Colin Barker, Jun 20 2018: (Start)

G.f.: 19*x*(1 + 14*x - 7*x^2 - 2*x^3) / (1 - x)^5.

a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n>5.

(End)