A196629 Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 1,3,2,0,4 for x=0,1,2,3,4

1, 2, 21, 327, 17278, 2140040, 651323279, 497248017421, 944403244013788, 4486207626875690795

Offset

1,2

Comments

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

Diagonal of A196636

Links

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

Example

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

Crossrefs

Sequence in context: A234525 A230382 A189489 * A196637 A240997 A241247

Adjacent sequences: A196626 A196627 A196628 * A196630 A196631 A196632

Keyword

nonn

Author

R. H. Hardin Oct 04 2011

Status

approved