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A202594
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Number of (n+2) X 3 binary arrays avoiding patterns 001 and 000 in rows and columns.
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1
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126, 510, 1968, 7722, 30114, 117708, 459690, 1795842, 7014816, 27402198, 107040102, 418129380, 1633329054, 6380241774, 24923005584, 97356232314, 380300658210, 1485560712012, 5803015490538, 22668201049266, 88548331298112
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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) = 2*a(n-1) +7*a(n-2) +2*a(n-3) -a(n-4).
Empirical g.f.: 6*x*(21 + 43*x + 11*x^2 - 6*x^3) / (1 - 2*x - 7*x^2 - 2*x^3 + x^4). - Colin Barker, Jun 01 2018
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EXAMPLE
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Some solutions for n=3:
..0..1..1....1..0..1....1..1..1....1..0..0....0..1..0....1..1..0....1..1..0
..1..0..0....1..1..1....1..0..1....0..1..1....1..1..1....0..1..1....1..0..1
..0..1..1....0..1..1....1..1..1....1..0..1....0..1..1....1..0..1....1..1..1
..1..1..0....1..1..1....1..1..1....1..1..0....1..0..1....0..1..1....0..1..1
..1..0..0....0..1..1....1..0..1....1..1..1....1..0..1....0..1..0....1..0..0
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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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