A196647 Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 3,4,0,2,1 for x=0,1,2,3,4

1, 7, 27, 391, 15289, 965315, 163282859, 65251102177, 58145917053607, 118692826575904321

Offset

1,2

Comments

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

Diagonal of A196653

Links

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

Example

Some solutions for n=4
..0..1..0..0....2..0..0..0....2..0..2..0....0..0..0..0....0..1..0..0
..1..4..1..2....0..2..2..2....0..2..1..0....2..0..0..0....1..4..1..0
..0..1..0..0....0..2..0..0....0..1..4..1....2..0..2..2....0..1..0..0
..0..0..0..0....0..2..0..0....0..0..1..0....0..0..2..0....2..0..0..2

Crossrefs

Sequence in context: A196323 A003148 A033910 * A274579 A152578 A300529

Adjacent sequences: A196644 A196645 A196646 * A196648 A196649 A196650

Keyword

nonn

Author

R. H. Hardin Oct 04 2011

Status

approved