A303309 Number of nX3 0..1 arrays with every element equal to 0, 1, 4, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

3, 3, 12, 11, 19, 34, 53, 83, 136, 223, 359, 578, 937, 1519, 2456, 3971, 6427, 10402, 16829, 27227, 44056, 71287, 115343, 186626, 301969, 488599, 790568, 1279163, 2069731, 3348898, 5418629, 8767523, 14186152, 22953679, 37139831, 60093506

Offset

1,1

Comments

Column 3 of A303314.

Links

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

Formula

Empirical: a(n) = a(n-1) +a(n-3) +a(n-4) for n>7

Example

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

Crossrefs

Cf. A303314.

Sequence in context: A066437 A153270 A065957 * A268774 A240801 A032308

Adjacent sequences: A303306 A303307 A303308 * A303310 A303311 A303312

Keyword

nonn

Author

R. H. Hardin, Apr 21 2018

Status

approved