A303964 Number of nX3 0..1 arrays with every element unequal to 0, 1, 3 or 5 king-move adjacent elements, with upper left element zero.

3, 9, 13, 26, 54, 101, 186, 361, 700, 1340, 2562, 4913, 9427, 18084, 34674, 66476, 127478, 244485, 468836, 899014, 1723966, 3305986, 6339698, 12157161, 23312919, 44705673, 85729179, 164397103, 315253197, 604539962, 1159286107, 2223085660

Offset

1,1

Comments

Column 3 of A303969.

Links

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

Formula

Empirical: a(n) = a(n-1) +2*a(n-3) +2*a(n-4) +a(n-5) +a(n-6) -a(n-7) -a(n-11) -a(n-12)

Example

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

Crossrefs

Cf. A303969.

Sequence in context: A113510 A163795 A079994 * A124825 A074938 A057260

Adjacent sequences: A303961 A303962 A303963 * A303965 A303966 A303967

Keyword

nonn

Author

R. H. Hardin, May 03 2018

Status

approved