A205190 Number of (n+1) X 6 0..1 arrays with the number of clockwise edge increases in every 2 X 2 subblock differing from each horizontal or vertical neighbor.

144, 168, 292, 384, 736, 896, 1568, 1920, 3392, 4224, 7520, 9344, 16608, 20608, 36608, 45440, 80736, 100224, 178080, 221056, 392768, 487552, 866272, 1075328, 1910624, 2371712, 4214016, 5230976, 9294304, 11537280, 20499232, 25446272, 45212480

Offset

1,1

Comments

Column 5 of A205193.

Links

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

Formula

Empirical: a(n) = 2*a(n-2) +a(n-6) for n>9.

Empirical g.f.: 4*x*(36 + 42*x + x^2 + 12*x^3 + 38*x^4 + 32*x^5 - 12*x^6 - 10*x^7 - 9*x^8) / (1 - 2*x^2 - x^6). - Colin Barker, Jun 11 2018

Example

Some solutions for n=4:
..0..0..1..1..0..0....0..0..1..1..1..0....0..0..1..0..0..0....0..1..1..0..0..1
..0..0..1..1..0..0....1..1..0..1..1..1....0..1..0..0..0..1....0..1..1..0..0..0
..1..1..0..0..1..1....1..1..1..0..1..1....1..0..0..0..1..0....1..0..0..1..0..0
..1..1..0..0..1..1....0..1..1..1..0..0....0..0..0..1..0..0....1..0..0..0..1..0
..1..0..1..1..0..1....1..0..1..1..0..0....0..0..1..0..0..0....0..1..0..0..0..1

Crossrefs

Cf. A205193.

Sequence in context: A044868 A162532 A294575 * A085426 A034289 A062917

Adjacent sequences: A205187 A205188 A205189 * A205191 A205192 A205193

Keyword

nonn

Author

R. H. Hardin, Jan 23 2012

Status

approved