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A207215
Number of n X n 0..2 arrays avoiding the pattern z z+1 z in any row or column
0
3, 81, 12534, 12584703, 86510224720, 4019515127529418, 1256433426475190769775, 2643803004141585682944365943
OFFSET
1,1
COMMENTS
Diagonal of A207221
EXAMPLE
Some solutions for n=4
..2..0..2..1....2..1..0..2....2..0..0..0....2..0..1..1....0..2..0..1
..1..1..1..0....1..1..1..2....0..1..1..0....2..1..0..1....2..0..1..1
..0..1..2..2....1..1..2..2....0..1..1..2....1..2..2..2....0..2..1..1
..0..0..0..2....1..1..0..1....2..2..0..1....1..0..0..0....2..0..0..1
CROSSREFS
Sequence in context: A207352 A207983 A207195 * A355071 A207544 A207311
KEYWORD
nonn
AUTHOR
R. H. Hardin Feb 16 2012
STATUS
approved