A304266 Number of nX4 0..1 arrays with every element unequal to 0, 1, 5 or 8 king-move adjacent elements, with upper left element zero.

5, 5, 10, 21, 50, 116, 259, 601, 1397, 3196, 7359, 17016, 39172, 90185, 208017, 479413, 1104402, 2545521, 5866934, 13519272, 31155923, 71803941, 165473389, 381338852, 878829251, 2025313404, 4667430712, 10756397233, 24788787493, 57127147381

Offset

1,1

Comments

Column 4 of A304270.

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) +a(n-4) -3*a(n-5) -3*a(n-6) for n>7

Example

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

Crossrefs

Cf. A304270.

Sequence in context: A022088 A245418 A082450 * A212344 A298181 A290332

Adjacent sequences: A304263 A304264 A304265 * A304267 A304268 A304269

Keyword

nonn

Author

R. H. Hardin, May 09 2018

Status

approved