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A208070
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Number of 5 X n 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 0 1 1 vertically.
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1
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12, 144, 216, 1008, 3696, 12960, 48840, 179520, 657000, 2423280, 8913456, 32769360, 120581784, 443565696, 1631571912, 6002079552, 22079078352, 81218792016, 298770650040, 1099049754720, 4042930839192, 14872226620512, 54708578740752
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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) = a(n-1) + 4*a(n-2) + 19*a(n-3) + 10*a(n-4) + 5*a(n-5) - 27*a(n-6) - 2*a(n-7) - 4*a(n-8) + 8*a(n-9) for n>11.
Empirical g.f.: 12*x*(1 + 11*x + 2*x^2 - x^3 - 86*x^4 - 31*x^5 - 51*x^6 + 114*x^7 + 4*x^8 + 24*x^9 - 32*x^10) / ((1 - 2*x - 4*x^2 - 8*x^3)*(1 + x + 2*x^2 - 3*x^3 - x^5 + x^6)). - Colin Barker, Jun 27 2018
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EXAMPLE
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Some solutions for n=4:
..0..0..1..1....1..1..0..0....1..1..0..1....0..0..1..1....0..1..1..0
..0..1..0..0....0..0..1..1....1..1..0..1....0..1..0..0....1..1..0..1
..0..0..1..1....1..1..0..0....1..1..0..1....0..0..1..1....0..1..0..0
..0..1..0..0....0..0..1..1....1..1..0..1....0..1..0..0....1..0..0..1
..0..0..1..1....0..1..0..0....0..1..0..1....0..0..1..0....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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