A317225 Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 3, 6, 7 or 8 king-move adjacent elements, with upper left element zero.

4, 21, 46, 150, 488, 1468, 4626, 14720, 45811, 143798, 453581, 1423094, 4469903, 14063611, 44197158, 138899518, 436737933, 1372924949, 4315682539, 13567748610, 42653241731, 134086614407, 421533391249, 1325188322229, 4166003679092

Offset

1,1

Comments

Column 3 of A317230.

Links

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

Formula

Empirical: a(n) = 3*a(n-1) +a(n-2) +7*a(n-3) -22*a(n-4) -23*a(n-5) +8*a(n-6) +29*a(n-7) +22*a(n-8) -20*a(n-9) -10*a(n-10) for n>12

Example

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

Crossrefs

Cf. A317230.

Sequence in context: A306048 A266149 A042223 * A273780 A033569 A201446

Adjacent sequences: A317222 A317223 A317224 * A317226 A317227 A317228

Keyword

nonn

Author

R. H. Hardin, Jul 24 2018

Status

approved