A302675 Number of nX3 0..1 arrays with every element equal to 0, 1, 4 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

3, 3, 8, 7, 11, 18, 29, 47, 76, 123, 199, 322, 521, 843, 1364, 2207, 3571, 5778, 9349, 15127, 24476, 39603, 64079, 103682, 167761, 271443, 439204, 710647, 1149851, 1860498, 3010349, 4870847, 7881196, 12752043, 20633239, 33385282, 54018521

Offset

1,1

Comments

Column 3 of A302680.

Links

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

Formula

Empirical: a(n) = a(n-1) +a(n-2) for n>5

Example

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

Crossrefs

Cf. A302680.

Sequence in context: A319133 A266560 A021751 * A305841 A331530 A199624

Adjacent sequences: A302672 A302673 A302674 * A302676 A302677 A302678

Keyword

nonn

Author

R. H. Hardin, Apr 11 2018

Status

approved