A221197 Number of n X 4 arrays of occupancy after each element moves to some horizontal, diagonal or antidiagonal neighbor, with no occupancy greater than 2.

4, 196, 9025, 427716, 20277009, 961434049, 45583531009, 2161117565476, 102456463038084, 4857310924636921, 230276948274214416, 10917021188851445889, 517556134069075087921, 24536386370101531606209

Offset: 1

Author

R. H. Hardin, Jan 04 2013

Keywords

• nonn

Comments

Column 4 of A221200.

Examples

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

Links

• R. H. Hardin, Table of n, a(n) for n = 1..25

Crossrefs

Cf. A221200.