A183732 1/16 the number of (n+1) X 4 0..7 arrays with every 2 X 2 subblock strictly increasing clockwise or counterclockwise with one decrease, and at least two adjacent blocks having the same increasing direction.

563, 13169, 469254, 32555965, 2610816897, 211915469907, 16635894447271, 1270931982853879, 94993985142144635, 6981985010723242050, 506415863251104840544, 36341705193868254651896, 2585229289237578869949797

Offset

1,1

Comments

Column 3 of A183738.

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

Example

Some solutions with the first block increasing clockwise for 3 X 4:
..3..6..4..3....4..5..4..3....5..1..7..6....2..4..6..4....5..1..0..7
..1..0..1..2....0..7..0..1....3..2..3..4....1..0..7..0....4..3..4..5
..5..7..6..3....5..6..4..3....6..1..7..5....4..5..6..4....5..2..0..7
...
...R..L..L.......R..L..L.......R..L..L.......R..R..L.......R..L..L...
...L..R..R.......L..R..R.......L..R..R.......L..L..R.......L..R..R...

Crossrefs

Sequence in context: A142759 A187849 A237029 * A014361 A274471 A252293

Adjacent sequences: A183729 A183730 A183731 * A183733 A183734 A183735

Keyword

nonn

Author

R. H. Hardin, Jan 06 2011

Status

approved