A317520 Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 3, 4, 5, 6 or 8 king-move adjacent elements, with upper left element zero.

4, 32, 248, 1921, 14892, 115446, 894961, 6937925, 53784248, 416946757, 3232258602, 25057145775, 194248243009, 1505853070853, 11673688450775, 90496878270178, 701550757601700, 5438568433511460, 42160921765806133, 326840297382217310

Offset

1,1

Comments

Column 3 of A317525.

Links

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

Formula

Empirical: a(n) = 8*a(n-1) -2*a(n-2) +a(n-3) -3*a(n-4)

Example

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

Crossrefs

Cf. A317525.

Sequence in context: A147551 A316803 A299649 * A300203 A273053 A303422

Adjacent sequences: A317517 A317518 A317519 * A317521 A317522 A317523

Keyword

nonn

Author

R. H. Hardin, Jul 30 2018

Status

approved