A241104 Number of nX4 0..2 arrays with no element equal to one or three horizontal or vertical neighbors, with new values 0..2 introduced in row major order.

4, 36, 294, 2436, 19814, 162776, 1333934, 10937316, 89651534, 734979136, 6025149574, 49393306556, 404916355574, 3319433387656, 27212098788254, 223079838087956, 1828767624421854, 14991902921730896, 122900877847563254

Offset: 1

Author

R. H. Hardin, Apr 16 2014

Keywords

• nonn

Comments

Column 4 of A241108

Examples

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

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 6*a(n-1) +21*a(n-2) -12*a(n-3) +8*a(n-4) -688*a(n-5) -1648*a(n-6) -768*a(n-7) -2304*a(n-8) +8192*a(n-9) +16384*a(n-10)