A199640 Number of n X n 0..2 arrays with values 0..2 introduced in row major order and each element equal to one or two horizontal and vertical neighbors

0, 3, 112, 29229, 32177372, 176701683386, 4539946639286136

Offset

1,2

Comments

Diagonal of A199647

Links

Table of n, a(n) for n=1..7.

Example

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

Crossrefs

Sequence in context: A169996 A054330 A024043 * A221618 A300814 A075051

Adjacent sequences: A199637 A199638 A199639 * A199641 A199642 A199643

Keyword

nonn

Author

R. H. Hardin Nov 08 2011

Status

approved