A301438 Number of nX3 0..1 arrays with every element equal to 0, 1, 2, 3, 4 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

4, 32, 232, 1708, 12576, 92616, 682084, 5023328, 36995208, 272457932, 2006565984, 14777720104, 108833207236, 801521947552, 5902954150952, 43473379381228, 320167608708256, 2357932581386376, 17365423319351844, 127890818185727968

Offset

1,1

Comments

Column 3 of A301443.

Links

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

Formula

Empirical: a(n) = 8*a(n-1) -4*a(n-2) -5*a(n-3)

Example

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

Crossrefs

Cf. A301443.

Sequence in context: A300799 A303457 A303451 * A331334 A301779 A370044

Adjacent sequences: A301435 A301436 A301437 * A301439 A301440 A301441

Keyword

nonn

Author

R. H. Hardin, Mar 21 2018

Status

approved