A221505 Number of nX3 arrays of occupancy after each element moves to some horizontal, diagonal or antidiagonal neighbor, without consecutive moves in the same direction.

0, 44, 664, 12495, 221614, 4010052, 72195950, 1301644004, 23457033692, 422775316892, 7619575554956, 137327198061432, 2475032964645724, 44607285582888084, 803952693936738644, 14489560929396894421

Offset: 1

Author

R. H. Hardin Jan 18 2013

Keywords

• nonn

Comments

Column 3 of A221507

Examples

			Some solutions for n=3
..0..0..0....0..3..0....0..4..0....1..1..0....0..1..1....0..1..0....0..0..0
..2..5..1....2..1..0....1..2..0....1..2..1....1..4..1....1..3..2....0..4..2
..0..1..0....1..2..0....0..0..2....0..3..0....0..1..0....0..2..0....1..2..0
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..20