A303310 Number of nX4 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.

5, 5, 17, 36, 74, 165, 361, 783, 1710, 3744, 8176, 17851, 39009, 85239, 186206, 406800, 888794, 1941803, 4242301, 9268393, 20249240, 44239542, 96652372, 211161719, 461336399, 1007905991, 2202025876, 4810883806, 10510594448, 22963055655

Offset

1,1

Comments

Column 4 of A303314.

Links

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

Formula

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

Example

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

Crossrefs

Cf. A303314.

Sequence in context: A100745 A283089 A283142 * A028892 A255448 A255445

Adjacent sequences: A303307 A303308 A303309 * A303311 A303312 A303313

Keyword

nonn

Author

R. H. Hardin, Apr 21 2018

Status

approved