A221824 T(n,k)=Number of nXk arrays of occupancy after each element stays put or moves to some horizontal or vertical neighbor, without consecutive moves in the same direction.

1, 3, 3, 6, 31, 6, 13, 252, 252, 13, 28, 2113, 6711, 2113, 28, 60, 17684, 190756, 190756, 17684, 60, 129, 147920, 5374720, 18636989, 5374720, 147920, 129, 277, 1237439, 151592441, 1804472268, 1804472268, 151592441, 1237439, 277, 595, 10351593

Offset: 1

Author

R. H. Hardin Jan 26 2013

Keywords

• nonn
• tabl

Comments

Table starts

....1........3............6.............13..............28..............60

....3.......31..........252...........2113...........17684..........147920

....6......252.........6711.........190756.........5374720.......151592441

...13.....2113.......190756.......18636989......1804472268....174820457922

...28....17684......5374720.....1804472268....597819977898.198296512455330

...60...147920....151592441...174820457922.198296512455330

..129..1237439...4274867564.16936005698353

..277.10351593.120554575328

..595.86594795

.1278

Examples

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

Links

• R. H. Hardin, Table of n, a(n) for n = 1..59

Crossrefs

Column 1 is A002478