A196796 Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 3,2,0,4,1 for x=0,1,2,3,4.

1, 7, 120, 7407, 1516652, 1029024216, 2336509457978, 17524876527067107, 436288315960458288785

Offset

1,2

Comments

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

Diagonal of A196802.

Links

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

Example

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

Crossrefs

Cf. A196802.

Sequence in context: A193785 A253276 A156955 * A196583 A197041 A283625

Adjacent sequences: A196793 A196794 A196795 * A196797 A196798 A196799

Keyword

nonn

Author

R. H. Hardin, Oct 06 2011

Status

approved