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A188708
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Number of 4 X n binary arrays without the pattern 0 0 diagonally or vertically.
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1
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8, 49, 304, 1876, 11556, 71152, 438048, 2696784, 16602304, 102209216, 629233216, 3873764352, 23848153088, 146816985344, 903853103104, 5564413613056, 34256339608576, 210893165924352, 1298326906544128, 7992922619695104
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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) = 8*a(n-1) - 12*a(n-2) + 4*a(n-3).
Empirical g.f.: x*(8 - 15*x + 8*x^2) / (1 - 8*x + 12*x^2 - 4*x^3). - Colin Barker, Apr 28 2018
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EXAMPLE
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Some solutions for 4 X 3:
1 0 0 1 1 1 1 1 1 0 1 1 1 1 1 1 1 1 0 1 1
0 1 1 0 0 0 1 1 0 1 1 1 1 1 0 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1 1 1 0 1 1 1 0 0 1 1 1
1 1 0 1 1 0 0 1 1 1 0 0 1 1 1 1 1 1 0 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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