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A188986
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Number of n X 3 binary arrays without the pattern 0 0 1 antidiagonally or horizontally.
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1
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7, 49, 295, 1793, 10871, 65937, 399911, 2425505, 14710935, 89223345, 541148807, 3282123457, 19906418039, 120734483153, 732267120743, 4441275782369, 26936796718423, 163374456576241, 990882967287879, 6009807624994561
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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) = 6*a(n-1) +a(n-2) -4*a(n-3) +2*a(n-4).
Empirical g.f.: x*(7 + 7*x - 6*x^2 + 2*x^3) / ((1 + x)*(1 - 7*x + 6*x^2 - 2*x^3)). - Colin Barker, May 01 2018
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EXAMPLE
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Some solutions for 4 X 3:
..1..0..0....0..1..0....0..0..0....1..1..0....0..0..0....1..0..0....1..0..0
..1..1..1....0..1..0....0..1..0....1..0..0....0..1..1....1..0..1....1..0..0
..0..0..0....1..1..0....1..1..1....0..1..1....1..0..0....0..1..1....0..0..0
..0..1..1....1..1..0....0..0..0....0..1..1....1..0..0....1..0..0....0..1..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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