A283859 Number of 3Xn 0..1 arrays with no 1 equal to more than three of its horizontal, diagonal and antidiagonal neighbors.

8, 64, 409, 2776, 19220, 131617, 901397, 6182652, 42392411, 290633973, 1992674389, 13662396421, 93672704694, 642244067806, 4403393953741, 30190811094903, 206996026936933, 1419218513242242, 9730530558373154, 66715043135972866

Offset

1,1

Comments

Row 3 of A283857.

Links

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

Formula

Empirical: a(n) = 5*a(n-1) +5*a(n-2) +50*a(n-3) +21*a(n-4) +11*a(n-5) -67*a(n-6) -229*a(n-7) -116*a(n-8) +41*a(n-9) +116*a(n-10) +66*a(n-11) +15*a(n-12) +a(n-13) -2*a(n-14)

Example

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

Crossrefs

Cf. A283857.

Sequence in context: A218267 A189105 A181214 * A222446 A239034 A213296

Adjacent sequences: A283856 A283857 A283858 * A283860 A283861 A283862

Keyword

nonn

Author

R. H. Hardin, Mar 17 2017

Status

approved