A230702 Number of (n+3)X(2+3) 0..2 white square subarrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 3, and upper left element zero.

8, 28, 244, 800, 6576, 21076, 173428, 554040, 4558536, 14555468, 119758148, 382358832, 3145930352, 10044068932, 82639468964, 263844008200, 2170826159272, 6930820136252, 57024624645332, 182063126310336, 1497958570841456

Offset: 1

Author

R. H. Hardin, Oct 28 2013

Keywords

• nonn

Comments

Column 2 of A230708

Examples

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

Links

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

Formula

Empirical: a(n) = 31*a(n-2) -126*a(n-4) +42*a(n-6) +79*a(n-8) -a(n-10) +8*a(n-12)