A305511 Number of nX3 0..1 arrays with every element unequal to 1, 2, 5, 6 or 8 king-move adjacent elements, with upper left element zero.

1, 2, 5, 6, 8, 19, 33, 60, 107, 204, 375, 677, 1253, 2329, 4252, 7824, 14454, 26591, 48908, 90088, 165947, 305495, 562342, 1035675, 1907146, 3511035, 6465055, 11904935, 21919763, 40360338, 74316988, 136840634, 251963379, 463940762

Offset

1,2

Comments

Column 3 of A305516.

Links

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

Formula

Empirical: a(n) = a(n-2) +4*a(n-3) +3*a(n-4) -4*a(n-6) -5*a(n-7) -a(n-8) -3*a(n-9) -2*a(n-10) for n>13

Example

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

Crossrefs

Cf. A305516.

Sequence in context: A326854 A097685 A136369 * A269472 A351830 A244272

Adjacent sequences: A305508 A305509 A305510 * A305512 A305513 A305514

Keyword

nonn

Author

R. H. Hardin, Jun 03 2018

Status

approved