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A206975
Number of 3Xn 0..3 arrays avoiding the pattern z-1 z-1 z in any row, column, nw-to-se diagonal or ne-to-sw antidiagonal
1
61, 3721, 180294, 8685113, 419203246, 20232472915, 976568167285, 47136598368813, 2275148053210870, 109814791045365561, 5300435987967164186, 255836290323951112260, 12348453565068178201467, 596022946181664047184360
OFFSET
1,1
COMMENTS
Row 3 of A206974
LINKS
EXAMPLE
Some solutions for n=4
..1..2..2..0....2..0..1..1....0..3..1..1....0..3..3..3....0..0..2..2
..3..0..1..1....2..0..0..2....1..2..2..0....1..3..1..2....0..1..0..1
..2..2..1..1....1..3..1..3....0..2..1..2....1..0..1..1....3..1..2..0
CROSSREFS
Sequence in context: A207231 A207224 A207011 * A206969 A206792 A206962
KEYWORD
nonn
AUTHOR
R. H. Hardin Feb 14 2012
STATUS
approved