A196803 Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 4,2,3,0,1 for x=0,1,2,3,4.

1, 1, 16, 193, 19449, 2535368, 1436535356, 2099296647197, 9043086011797968, 109561680407727718539

Offset

1,3

Comments

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

Diagonal of A196809.

Links

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

Example

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

Crossrefs

Cf. A196809.

Sequence in context: A374070 A016178 A081202 * A292785 A081185 A159517

Adjacent sequences: A196800 A196801 A196802 * A196804 A196805 A196806

Keyword

nonn

Author

R. H. Hardin, Oct 06 2011

Status

approved