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A206856
Number of n X n 0..2 arrays avoiding the pattern z z+1 z in any row, column, diagonal or antidiagonal
0
3, 81, 11092, 7598355, 31208037240, 729358354663001, 92792498733436652359
OFFSET
1,1
COMMENTS
Diagonal of A206863
EXAMPLE
Some solutions for n=4
..0..2..2..2....2..0..1..2....0..2..2..0....0..2..0..1....2..2..2..1
..1..1..0..2....0..2..2..0....1..0..0..0....2..0..1..1....2..1..0..2
..2..0..1..1....2..2..0..1....2..2..1..2....0..2..1..1....2..0..0..2
..2..2..1..2....2..1..2..2....0..1..2..2....2..0..0..1....1..0..1..2
CROSSREFS
Sequence in context: A223783 A223969 A207202 * A206951 A206726 A207352
KEYWORD
nonn
AUTHOR
R. H. Hardin Feb 13 2012
STATUS
approved