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A196487
Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 2,3,0,1,4 for x=0,1,2,3,4
0
1, 1, 9, 99, 2862, 188603, 28338246, 10179007465, 8440119388684, 16385876855589022, 74005549246712939357, 780142920501811666245635
OFFSET
1,3
COMMENTS
Every 0 is next to 0 2's, every 1 is next to 1 3's, every 2 is next to 2 0's, every 3 is next to 3 1's, every 4 is next to 4 4's
Diagonal of A196493
EXAMPLE
Some solutions for n=4
..0..1..3..1....1..1..3..1....0..0..0..0....1..3..1..0....1..3..1..0
..0..0..1..0....3..1..1..1....1..1..3..1....0..1..1..0....1..1..0..1
..1..3..1..0....1..0..1..3....3..1..1..0....0..1..3..1....3..1..1..3
..0..1..0..0....0..0..0..1....1..0..0..0....0..0..0..0....1..0..0..1
CROSSREFS
Sequence in context: A070068 A068668 A035027 * A262540 A265203 A078238
KEYWORD
nonn
AUTHOR
R. H. Hardin Oct 03 2011
STATUS
approved