A197228 Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 4,3,0,1,2 for x=0,1,2,3,4

1, 7, 55, 2117, 249929, 98514881, 126615582841, 511052139999591

Offset

1,2

Comments

Every 0 is next to 0 4'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 2's

Diagonal of A197235

Links

Table of n, a(n) for n=1..8.

Example

Some solutions for n=4
..0..0..0..0....2..0..0..2....2..0..1..0....0..1..2..0....0..0..0..1
..2..0..0..1....0..0..1..0....0..0..3..1....1..3..0..0....0..0..1..3
..2..0..1..3....2..1..3..1....0..0..1..0....0..1..0..0....0..0..2..1
..0..0..0..1....0..0..0..0....2..0..0..0....2..0..0..0....0..0..0..0

Crossrefs

Sequence in context: A117993 A055056 A305282 * A009521 A116120 A056719

Adjacent sequences: A197225 A197226 A197227 * A197229 A197230 A197231

Keyword

nonn

Author

R. H. Hardin Oct 12 2011

Status

approved