A197084 Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 4,3,2,0,1 for x=0,1,2,3,4

1, 2, 25, 631, 71867, 21996614, 21989908007, 68650847877254, 670636652224421841

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

Diagonal of A197090

Links

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

Example

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

Crossrefs

Sequence in context: A322727 A090733 A330767 * A366038 A337153 A119829

Adjacent sequences: A197081 A197082 A197083 * A197085 A197086 A197087

Keyword

nonn

Author

R. H. Hardin Oct 10 2011

Status

approved