A204946 Number of (n+2)X(n+2) 0..2 arrays with every 3X3 subblock having three equal elements in a row horizontally, vertically, diagonally or antidiagonally exactly two different ways, and new values 0..2 introduced in row major order

506, 41353, 7062216, 1616210763, 1021853269087

Offset

1,1

Comments

Diagonal of A204954

Links

Table of n, a(n) for n=1..5.

Example

Some solutions for n=3
..0..0..0..0..0....0..0..0..0..0....0..0..1..0..0....0..0..1..2..2
..0..1..2..1..0....0..0..0..0..0....1..0..2..1..0....0..0..0..2..2
..1..1..1..1..1....1..1..2..1..1....2..0..0..0..0....2..0..1..2..2
..0..0..0..0..0....2..2..2..2..2....0..0..0..1..2....2..2..2..2..0
..0..2..1..0..0....1..0..2..2..0....1..1..1..1..1....1..0..2..2..1

Crossrefs

Sequence in context: A204947 A295992 A122267 * A023913 A035848 A028685

Adjacent sequences: A204943 A204944 A204945 * A204947 A204948 A204949

Keyword

nonn

Author

R. H. Hardin Jan 20 2012

Status

approved