A317736 Number of nX3 0..1 arrays with every element unequal to 2 or 3 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

0, 1, 1, 3, 2, 4, 6, 14, 14, 22, 43, 68, 82, 147, 246, 360, 516, 888, 1385, 2046, 3165, 5185, 7888, 11991, 18930, 29960, 45643, 70736, 111396, 173435, 266587, 416156, 650940, 1008681, 1561889, 2439244, 3797561, 5886887, 9150037, 14265005, 22165953

Offset

1,4

Comments

Column 3 of A317741.

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) +7*a(n-4) +7*a(n-5) +4*a(n-6) -5*a(n-7) -10*a(n-8) -9*a(n-9) -3*a(n-10) for n>13

Example

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

Crossrefs

Cf. A317741.

Sequence in context: A085346 A121861 A338213 * A060006 A368254 A368261

Adjacent sequences: A317733 A317734 A317735 * A317737 A317738 A317739

Keyword

nonn

Author

R. H. Hardin, Aug 05 2018

Status

approved