A197091 Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 4,4,0,0,1 for x=0,1,2,3,4

1, 7, 74, 3477, 457357, 183439730, 227951140324, 864930843239459, 10066466828015680364, 359074320635161326740035

Offset

1,2

Comments

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

Diagonal of A197098

Links

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

Example

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

Crossrefs

Sequence in context: A323322 A356589 A326221 * A174243 A157706 A197763

Adjacent sequences: A197088 A197089 A197090 * A197092 A197093 A197094

Keyword

nonn

Author

R. H. Hardin Oct 10 2011

Status

approved