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

1,1

Comments

Diagonal of A203835

Links

Table of n, a(n) for n=1..8.

Example

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

Crossrefs

Sequence in context: A215859 A143170 A328351 * A318221 A162885 A163231

Adjacent sequences: A203825 A203826 A203827 * A203829 A203830 A203831

Keyword

nonn

Author

R. H. Hardin Jan 06 2012

Status

approved