A206129 Number of (n+1) X (n+1) 0..3 arrays with every 2 X 3 or 3 X 2 subblock having exactly three counterclockwise and three clockwise edge increases.

256, 6668, 2761756, 5465582068, 51845281856116, 2363085244017636372, 518342328616619031217028, 547728179121316322465056282220

Offset

1,1

Comments

Diagonal of A206137.

Links

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

Example

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

Crossrefs

Sequence in context: A056585 A321818 A231307 * A236214 A232959 A187955

Adjacent sequences: A206126 A206127 A206128 * A206130 A206131 A206132

Keyword

nonn

Author

R. H. Hardin, Feb 04 2012

Status

approved