A305764 Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 3, 4 or 7 king-move adjacent elements, with upper left element zero.

4, 30, 141, 684, 3282, 15874, 76613, 370087, 1787161, 8631009, 41682223, 201299206, 972149367, 4694874104, 22673308188, 109497913757, 528806506293, 2553805037346, 12333282715847, 59562049771856, 287647486358008

Offset

1,1

Comments

Column 3 of A305769.

Links

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

Formula

Empirical: a(n) = 3*a(n-1) +9*a(n-2) -6*a(n-4) +12*a(n-5) -3*a(n-6) -27*a(n-7) +17*a(n-8) -4*a(n-9) -7*a(n-10) +a(n-11)

Example

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

Crossrefs

Cf. A305769.

Sequence in context: A005715 A281950 A316178 * A317113 A123351 A305525

Adjacent sequences: A305761 A305762 A305763 * A305765 A305766 A305767

Keyword

nonn

Author

R. H. Hardin, Jun 10 2018

Status

approved