A317261 Number of nX3 0..1 arrays with every element unequal to 0, 1, 3, 4, 6, 7 or 8 king-move adjacent elements, with upper left element zero.

3, 7, 10, 21, 46, 91, 186, 409, 892, 1931, 4236, 9363, 20792, 46525, 104832, 237487, 540898, 1238373, 2848246, 6577977, 15248530, 35464687, 82722630, 193446597, 453383480, 1064658303, 2504274032, 5899032191, 13912945708, 32848848465

Offset

1,1

Comments

Column 3 of A317266.

Links

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

Formula

Empirical: a(n) = 4*a(n-1) -3*a(n-2) +a(n-3) -12*a(n-4) +11*a(n-5) -6*a(n-6) +20*a(n-7) -17*a(n-8) +20*a(n-9) +a(n-10) +7*a(n-11) -30*a(n-12) -11*a(n-13) -8*a(n-14) +8*a(n-15) +8*a(n-16)

Example

Some solutions for n=5
..0..0..1. .0..1..1. .0..0..0. .0..0..1. .0..0..0. .0..0..1. .0..0..0
..0..1..1. .1..1..1. .0..0..0. .0..0..0. .0..1..0. .0..1..1. .1..0..0
..1..1..1. .1..1..1. .0..0..0. .0..0..0. .0..0..0. .0..0..0. .1..1..0
..1..1..1. .0..1..1. .1..0..0. .0..0..1. .0..0..0. .0..0..1. .1..1..1
..1..1..1. .0..0..1. .1..1..0. .0..1..1. .1..0..0. .0..1..1. .1..1..1

Crossrefs

Cf. A317266.

Sequence in context: A279912 A305477 A316306 * A363643 A024464 A127277

Adjacent sequences: A317258 A317259 A317260 * A317262 A317263 A317264

Keyword

nonn

Author

R. H. Hardin, Jul 25 2018

Status

approved