A203828 Number of (n+1)X(n+1) 0..2 arrays with every 2X2 subblock having equal diagonal elements or equal antidiagonal elements.

45, 1971, 270333, 119606211, 173185290765, 827309554361235, 13102412661293146461, 690154670186627261773347

Offset: 1

Author

R. H. Hardin Jan 06 2012

Keywords

• nonn

Comments

Diagonal of A203835

Examples

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