A205641 Number of (n+1)X8 0..3 arrays with every 2 X 2 subblock having the number of clockwise edge increases equal to the number of counterclockwise edge increases in its adjacent leftward and upward neighbors.

158804736, 13444055224, 4782966551464, 3046981775525932, 2083971490096234516, 1438784646024287898832, 995980221935339574016820, 690272631599920646789218256

Offset

1,1

Comments

Column 7 of A205642.

Links

Table of n, a(n) for n=1..8.

Example

Some solutions for n=4:
..3..1..1..2..1..2..3..0....2..3..3..0..3..3..3..1....1..1..2..1..3..1..2..1
..3..2..2..2..0..1..2..2....2..3..0..0..3..0..3..3....1..2..2..1..1..1..2..1
..3..2..0..1..3..0..2..3....2..3..3..3..3..3..3..0....1..1..1..1..2..2..2..1
..2..2..3..0..1..0..2..3....2..2..2..2..2..2..3..3....3..1..0..1..1..1..1..1
..3..0..1..3..1..0..2..3....2..1..1..1..1..2..2..2....1..1..0..0..0..0..0..0

Crossrefs

Sequence in context: A204605 A289248 A251489 * A118078 A365019 A151695

Adjacent sequences: A205638 A205639 A205640 * A205642 A205643 A205644

Keyword

nonn

Author

R. H. Hardin, Jan 29 2012

Status

approved