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A229407
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Number of nX3 0..3 arrays avoiding 11 horizontally, 22 vertically, 33 antidiagonally and 00 diagonally
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1
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57, 1756, 53538, 1629298, 49788258, 1519840402, 46408035676, 1416912709750, 43262165219520, 1320895600914374, 40330198228444030, 1231378827675817778, 37596999339380782420, 1147927946466853457658, 35049037211821475282406
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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Empirical: a(n) = 18*a(n-1) +376*a(n-2) +224*a(n-3) -1664*a(n-4) +36983*a(n-5) -181958*a(n-6) +100599*a(n-7) +484260*a(n-8) -503501*a(n-9) -354823*a(n-10) +399643*a(n-11) +243696*a(n-12) +20412*a(n-13)
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EXAMPLE
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Some solutions for n=3
..1..0..1....0..0..1....3..2..2....2..0..0....1..3..0....3..1..2....3..2..0
..3..3..3....0..2..1....0..3..1....1..3..1....1..3..0....1..0..0....2..0..2
..0..2..0....2..3..2....2..3..3....0..3..1....0..0..2....1..0..1....3..3..1
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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