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A208030
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Number of 5 X n 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 0 and 1 0 1 vertically.
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1
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13, 169, 741, 4823, 26845, 158847, 917293, 5349227, 31070195, 180762387, 1050937017, 6111802359, 35539343255, 206667375733, 1201779520773, 6988465966781, 40638445631355, 236315996095075, 1374196381175527
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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) = 3*a(n-1) + 19*a(n-2) - 9*a(n-3) - 42*a(n-4) + 31*a(n-5) + 3*a(n-6) - 4*a(n-7).
Empirical g.f.: 13*x*(1 + 10*x - x^2 - 38*x^3 + 28*x^4 + 3*x^5 - 4*x^6) / ((1 - x)*(1 - 2*x - 21*x^2 - 12*x^3 + 30*x^4 - x^5 - 4*x^6)). - Colin Barker, Jun 26 2018
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EXAMPLE
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Some solutions for n=4:
..0..1..1..0....0..1..1..0....1..1..1..0....0..1..1..1....0..1..0..0
..1..0..1..0....0..1..0..1....0..1..0..0....1..0..1..0....1..1..1..0
..1..0..1..1....1..1..0..1....0..1..0..1....1..0..1..0....1..1..0..1
..1..1..1..1....1..0..1..0....1..0..1..0....0..1..0..1....1..1..0..0
..1..1..1..1....1..0..1..0....1..0..1..0....0..1..0..0....1..1..1..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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