A183711 1/20 of the number of (n+1) X (n+1) 0..4 arrays with every 2 X 2 subblock strictly increasing clockwise or counterclockwise with one decrease.

2, 17, 224, 5362, 224640, 16823812, 2239265280, 532844962952, 226169896329216, 171735135418632976, 232966965220983791616, 565591167958003196615968, 2455196078535760615522467840

Offset

1,1

Comments

Diagonal of A183719.

Links

Table of n, a(n) for n=1..13.

Example

Some solutions for 3 X 3:
..0..1..0....3..2..3....2..3..1....4..3..0....4..0..4....4..0..3....0..1..0
..3..2..3....4..0..4....1..4..0....1..2..1....2..1..2....2..1..2....4..3..4
..4..1..0....3..2..3....2..3..1....0..3..0....3..0..3....3..4..3....1..2..1
...
...R..L.......L..R.......R..L.......L..R.......R..L.......R..L.......R..L...
...L..R.......R..L.......L..R.......R..L.......L..R.......L..R.......L..R...

Crossrefs

Sequence in context: A004029 A114268 A144208 * A058239 A006227 A307289

Adjacent sequences: A183708 A183709 A183710 * A183712 A183713 A183714

Keyword

nonn

Author

R. H. Hardin, Jan 06 2011

Status

approved