A197744 Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 3,3,0,1,0 for x=0,1,2,3,4

1, 7, 66, 1317, 115795, 26488736, 16946352492, 30667098889607, 150836015759040225

Offset

1,2

Comments

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

Diagonal of A197750

Links

Table of n, a(n) for n=1..9.

Example

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

Crossrefs

Sequence in context: A003286 A244602 A223889 * A052351 A210476 A217095

Adjacent sequences: A197741 A197742 A197743 * A197745 A197746 A197747

Keyword

nonn

Author

R. H. Hardin Oct 17 2011

Status

approved