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A197665
Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 4,0,1,0,1 for x=0,1,2,3,4
0
1, 9, 95, 5005, 709083, 311676959, 417293944115, 1717065757366333
OFFSET
1,2
COMMENTS
Every 0 is next to 0 4's, every 1 is next to 1 0's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 1's
Diagonal of A197672
EXAMPLE
Some solutions for n=4
..2..1..1..1....1..0..0..0....0..1..2..0....0..0..3..0....0..1..2..0
..1..0..0..0....2..0..3..0....1..4..1..0....0..0..0..3....0..1..1..0
..1..0..0..3....1..1..2..0....1..1..1..0....0..0..3..0....1..1..2..0
..1..0..3..0....0..2..1..0....0..0..2..1....1..1..2..1....1..0..0..0
CROSSREFS
Sequence in context: A337269 A065456 A052389 * A064504 A090448 A264219
KEYWORD
nonn
AUTHOR
R. H. Hardin Oct 17 2011
STATUS
approved