A196898 Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 4,3,1,0,2 for x=0,1,2,3,4

1, 1, 20, 401, 37194, 9855864, 8351540397, 21716826606543, 177451785967252194

Offset

1,3

Comments

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

Diagonal of A196904

Links

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

Example

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

Crossrefs

Sequence in context: A041181 A041762 A196740 * A355966 A068772 A230349

Adjacent sequences: A196895 A196896 A196897 * A196899 A196900 A196901

Keyword

nonn

Author

R. H. Hardin Oct 07 2011

Status

approved