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A206894
Number of n X n 0..3 arrays avoiding the pattern z-2 z-1 z in any row, column or nw-to-se diagonal
0
4, 256, 211548, 2408811358, 369048436354154, 768965608329861602588, 21727183867324671091396681434
OFFSET
1,1
COMMENTS
Diagonal of A206900
EXAMPLE
Some solutions for n=4
..2..3..1..3....1..0..0..0....3..1..1..1....1..3..2..1....0..0..1..3
..2..2..1..1....0..3..1..2....3..3..3..1....1..1..0..3....0..3..3..0
..3..2..0..1....1..0..1..3....3..1..3..3....2..3..3..0....1..0..1..3
..0..3..3..1....1..3..3..1....3..1..1..1....0..2..1..3....1..1..0..0
CROSSREFS
Sequence in context: A207128 A223579 A206832 * A207284 A229100 A060757
KEYWORD
nonn
AUTHOR
R. H. Hardin Feb 13 2012
STATUS
approved