A317866 Number of nX3 0..1 arrays with every element unequal to 2, 3 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

0, 1, 1, 6, 4, 5, 10, 36, 34, 43, 100, 238, 256, 404, 834, 1650, 2029, 3475, 6656, 11911, 16264, 28718, 52073, 88566, 130729, 231474, 404502, 672893, 1047207, 1838676, 3138625, 5185889, 8345365, 14484260, 24389857, 40314863, 66171913, 113604305

Offset

1,4

Comments

Column 3 of A317871.

Links

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

Formula

Empirical: a(n) = -a(n-1) -a(n-2) +2*a(n-3) +9*a(n-4) +9*a(n-5) +6*a(n-6) -9*a(n-7) -15*a(n-8) -14*a(n-9) +2*a(n-10) +10*a(n-11) +3*a(n-12) -3*a(n-13) -6*a(n-14) +a(n-15) +a(n-17) -a(n-18)

Example

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

Crossrefs

Cf. A317871.

Sequence in context: A177159 A361605 A356479 * A309977 A349700 A201408

Adjacent sequences: A317863 A317864 A317865 * A317867 A317868 A317869

Keyword

nonn

Author

R. H. Hardin, Aug 09 2018

Status

approved