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A197273
Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 2,0,1,1,1 for x=0,1,2,3,4
0
1, 9, 34, 627, 16890, 1276986, 209785488, 84453386767, 71088592371829
OFFSET
1,2
COMMENTS
Every 0 is next to 0 2's, every 1 is next to 1 0's, every 2 is next to 2 1's, every 3 is next to 3 1's, every 4 is next to 4 1's
Diagonal of A197280
EXAMPLE
Some solutions containing all values 0 to 4 for n=4
..1..0..1..2....0..1..1..0....1..3..1..0....2..1..0..1....1..0..1..2
..1..1..4..1....1..4..1..0....0..1..4..1....1..4..1..3....3..1..4..1
..0..1..1..0....3..1..4..1....1..4..1..1....0..1..4..1....1..4..1..0
..0..1..3..1....1..0..1..2....2..1..0..0....0..1..1..0....0..1..1..0
CROSSREFS
Sequence in context: A204426 A154393 A119389 * A067960 A119757 A003865
KEYWORD
nonn
AUTHOR
R. H. Hardin Oct 12 2011
STATUS
approved