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A207457
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Number of 6 X n 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 1 0 1 vertically.
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1
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12, 144, 396, 2460, 9216, 46956, 196812, 932688, 4086060, 18819228, 83939328, 382160076, 1717133964, 7780911120, 35067371724, 158593617564, 715647771648, 3233959733292, 14600607874380, 65957362026192, 297845692391532
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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) + 16*a(n-2) + 5*a(n-3) - 25*a(n-4).
Empirical g.f.: 12*x*(1 + 11*x + 5*x^2 - 25*x^3) / (1 - x - 16*x^2 - 5*x^3 + 25*x^4). - Colin Barker, Jun 23 2018
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EXAMPLE
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Some solutions for n=5:
1 0 1 1 0 0 1 1 1 1 1 0 1 0 1 1 0 1 0 1
1 1 0 1 1 0 1 0 1 1 0 1 1 1 0 1 0 1 0 1
0 1 0 1 0 0 1 0 1 0 0 1 0 1 0 1 0 1 0 1
0 1 0 1 0 0 1 0 1 0 0 1 0 1 0 1 0 1 0 0
0 1 0 1 0 0 1 0 1 0 0 1 0 1 0 1 0 1 0 0
0 1 0 1 0 0 1 0 1 0 0 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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