A316415 Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 5, 6 or 8 king-move adjacent elements, with upper left element zero.

4, 5, 14, 27, 66, 180, 484, 1261, 3346, 8912, 23666, 62840, 166959, 443676, 1178829, 3132091, 8322214, 22112722, 58754687, 156114566, 414806153, 1102165608, 2928521067, 7781259792, 20675285518, 54935502703, 145967000962, 387843280136

Offset

1,1

Comments

Column 3 of A316420.

Links

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

Formula

Empirical: a(n) = a(n-1) +3*a(n-2) +4*a(n-3) +2*a(n-4) -3*a(n-5) -9*a(n-6) -6*a(n-7) for n>10

Example

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

Crossrefs

Cf. A316420.

Sequence in context: A200177 A241863 A350527 * A007084 A216243 A093862

Adjacent sequences: A316412 A316413 A316414 * A316416 A316417 A316418

Keyword

nonn

Author

R. H. Hardin, Jul 02 2018

Status

approved