A205816 Number of (n+1) X (n+1) 0..2 arrays with the number of clockwise edge increases in every 2 X 2 subblock unequal to the number of counterclockwise edge increases.

24, 216, 2880, 67944, 2791080, 206195280, 27196042704, 6437088838008, 2723887997403024, 2064821553536444652, 2798458452635665138464

Offset

1,1

Comments

Diagonal of A205823.

Links

Table of n, a(n) for n=1..11.

Example

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

Crossrefs

Sequence in context: A104670 A205968 A232474 * A138406 A042112 A297679

Adjacent sequences: A205813 A205814 A205815 * A205817 A205818 A205819

Keyword

nonn

Author

R. H. Hardin, Feb 01 2012

Status

approved