A316540 Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 4, 7 or 8 king-move adjacent elements, with upper left element zero.

4, 12, 26, 53, 187, 484, 1262, 3570, 9751, 26557, 72773, 199700, 546815, 1496934, 4102867, 11240497, 30788845, 84352649, 231098249, 633098685, 1734421624, 4751634729, 13017502145, 35662487018, 97700580311, 267659337870

Offset

1,1

Comments

Column 3 of A316545.

Links

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

Formula

Empirical: a(n) = a(n-1) +3*a(n-2) +8*a(n-3) -a(n-4) -12*a(n-5) -26*a(n-6) -2*a(n-7) +10*a(n-8) +15*a(n-9) -a(n-10) +6*a(n-11) for n>12

Example

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

Crossrefs

Cf. A316545.

Sequence in context: A057307 A009844 A264100 * A066185 A330704 A239940

Adjacent sequences: A316537 A316538 A316539 * A316541 A316542 A316543

Keyword

nonn

Author

R. H. Hardin, Jul 06 2018

Status

approved