A197173 Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 2,2,1,0,0 for x=0,1,2,3,4

1, 5, 41, 969, 92206, 22335117, 16686610707, 35396160304609, 218937410204781995, 3910004408912399352584

Offset

1,2

Comments

Every 0 is next to 0 2's, every 1 is next to 1 2's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 0's

Diagonal of A197180

Links

Table of n, a(n) for n=1..10.

Example

Some solutions containing all values 0 to 4 for n=4
..0..0..1..2....0..1..2..1....1..2..1..0....0..0..0..0....0..0..1..2
..0..4..0..1....3..0..3..0....0..3..0..0....0..4..0..0....3..0..0..1
..0..0..4..0....0..4..0..1....3..0..4..0....3..0..0..1....0..4..0..0
..0..3..0..0....0..0..1..2....0..0..0..0....0..0..1..2....0..0..0..0

Crossrefs

Sequence in context: A181033 A189997 A342439 * A052113 A318294 A065035

Adjacent sequences: A197170 A197171 A197172 * A197174 A197175 A197176

Keyword

nonn

Author

R. H. Hardin Oct 11 2011

Status

approved