A304226 Number of nX4 0..1 arrays with every element unequal to 0, 1, 2 or 7 king-move adjacent elements, with upper left element zero.

8, 5, 6, 11, 20, 46, 97, 189, 395, 836, 1701, 3492, 7284, 15033, 30913, 63989, 132350, 272947, 563756, 1165374, 2406457, 4969281, 10266751, 21207248, 43798629, 90470888, 186881300, 385997321, 797284757, 1646862265, 3401654354, 7026194587

Offset

1,1

Comments

Column 4 of A304230.

Links

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

Formula

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

Example

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

Crossrefs

Cf. A304230.

Sequence in context: A365281 A021898 A020786 * A019868 A121472 A117039

Adjacent sequences: A304223 A304224 A304225 * A304227 A304228 A304229

Keyword

nonn

Author

R. H. Hardin, May 08 2018

Status

approved