A297910 Number of nX3 0..1 arrays with every element equal to 0, 2, 3 or 4 king-move adjacent elements, with upper left element zero.

1, 12, 10, 49, 144, 481, 2016, 7730, 30637, 122459, 486274, 1937553, 7719764, 30746715, 122495655, 487999537, 1944079833, 7744935218, 30854501570, 122919184440, 489690085219, 1950844654280, 7771845245990, 30961758474839

Offset

1,2

Comments

Column 3 of A297915.

Links

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

Formula

Empirical: a(n) = 4*a(n-1) +a(n-2) -17*a(n-4) -2*a(n-6) +3*a(n-7) +53*a(n-8) -11*a(n-9) -60*a(n-10) +14*a(n-11) +20*a(n-12) -4*a(n-13) for n>15

Example

Some solutions for n=7
..0..0..0. .0..1..0. .0..1..0. .0..0..0. .0..0..1. .0..1..1. .0..0..1
..0..1..0. .1..1..1. .1..1..1. .0..1..0. .0..1..1. .0..0..1. .1..0..0
..0..1..1. .1..0..0. .0..0..0. .1..1..0. .0..0..1. .0..1..1. .1..1..1
..0..0..1. .0..1..0. .0..1..0. .1..0..1. .1..0..0. .1..0..1. .0..0..1
..0..1..1. .0..1..1. .0..1..1. .0..1..0. .1..1..0. .1..0..0. .0..1..1
..0..1..1. .0..1..1. .1..0..0. .1..0..1. .0..0..0. .1..0..0. .0..0..0
..0..0..1. .0..0..1. .1..1..0. .1..1..1. .1..0..1. .1..1..0. .1..0..1

Crossrefs

Cf. A297915.

Sequence in context: A262965 A094450 A307166 * A298503 A038336 A236506

Adjacent sequences: A297907 A297908 A297909 * A297911 A297912 A297913

Keyword

nonn

Author

R. H. Hardin, Jan 08 2018

Status

approved