

A197091


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


0




OFFSET

1,2


COMMENTS

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


LINKS



EXAMPLE

Some solutions containing all values 0 to 4 for n=4
..0..1..0..2....2..0..1..0....0..0..0..0....0..1..0..0....0..1..0..0
..1..4..1..0....0..1..4..1....3..0..1..0....1..4..1..0....1..4..1..0
..0..1..0..0....3..0..1..0....0..1..4..1....0..1..0..3....0..1..0..0
..2..0..3..0....0..0..0..0....2..0..1..0....2..0..0..0....2..0..3..0


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



