A208391 Number of nX7 0..2 arrays with new values 0..2 introduced in row major order and no element equal to more than two of its immediate leftward or upward or right-upward antidiagonal neighbors.

365, 667476, 1233536544, 2278687944204, 4209452449879284, 7776176148498498768, 14365030966055594634024, 26536707847376158191040692, 49021604272173916567275685956, 90558244799577286285888604547504

Offset: 1

Author

R. H. Hardin Feb 25 2012

Keywords

• nonn

Comments

Column 7 of A208392

Examples

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

Links

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

Formula

Empirical: a(n) = 1899*a(n-1) -96485*a(n-2) +1863135*a(n-3) -19545624*a(n-4) [phone]*a(n-5) -573780996*a(n-6) [phone]*a(n-7) -3625252848*a(n-8) [phone]*a(n-9) [phone]*a(n-10) for n>12