A208283 Number of n X 4 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 1 1 0 vertically.

10, 100, 378, 984, 2090, 3900, 6650, 10608, 16074, 23380, 32890, 45000, 60138, 78764, 101370, 128480, 160650, 198468, 242554, 293560, 352170, 419100, 495098, 580944, 677450, 785460, 905850, 1039528, 1187434, 1350540, 1529850, 1726400, 1941258

Offset

1,1

Comments

Column 4 of A208287.

Links

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

Formula

Empirical: a(n) = (4/3)*n^4 + 10*n^3 + (2/3)*n^2 - 2*n.

Conjectures from Colin Barker, Jun 29 2018: (Start)

G.f.: 2*x*(5 + 25*x - 11*x^2 - 3*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)

Example

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

Crossrefs

Cf. A208287.

Sequence in context: A207950 A207859 A207809 * A208416 A208024 A207804

Adjacent sequences: A208280 A208281 A208282 * A208284 A208285 A208286

Keyword

nonn

Author

R. H. Hardin, Feb 25 2012

Status

approved