A304136 Number of n X 3 0..1 arrays with every element unequal to 0, 2, 3 or 6 king-move adjacent elements, with upper left element zero.

1, 7, 5, 9, 15, 16, 33, 57, 62, 133, 231, 256, 549, 953, 1074, 2281, 3951, 4524, 9497, 16409, 19078, 39581, 68215, 80488, 165085, 283801, 339658, 688993, 1181567, 1433652, 2877361, 4922681, 6052414, 12023669, 20522759, 25555920, 50272981

Offset

1,2

Comments

Column 3 of A304141.

Links

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

Formula

Empirical: a(n) = a(n-1) +a(n-2) +5*a(n-3) -5*a(n-4) -5*a(n-5) -4*a(n-6) +4*a(n-7) +4*a(n-8) for n>10.

Example

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

Crossrefs

Cf. A304141.

Sequence in context: A351212 A323669 A356526 * A305042 A247870 A367689

Adjacent sequences: A304133 A304134 A304135 * A304137 A304138 A304139

Keyword

nonn

Author

R. H. Hardin, May 07 2018

Status

approved