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A228751
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Number of n X 5 binary arrays with top left element equal to 1 and no two ones adjacent horizontally or antidiagonally.
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1
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5, 50, 482, 4599, 43862, 418370, 3990739, 38067290, 363121586, 3463797759, 33040991486, 315176359538, 3006451507579, 28678390419458, 273561730649282, 2609491655262279, 24891810279661862, 237441732282894050
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OFFSET
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1,1
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LINKS
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FORMULA
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Empirical: a(n) = 13*a(n-1) - 36*a(n-2) + 29*a(n-3) - 5*a(n-4) for n>5.
Empirical g.f.: x*(5 - 15*x + 12*x^2 - 12*x^3 + 2*x^4) / ((1 - x)*(1 - 12*x + 24*x^2 - 5*x^3)). - Colin Barker, Sep 12 2018
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EXAMPLE
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Some solutions for n=4:
..1..0..1..0..0....1..0..0..0..0....1..0..0..0..0....1..0..0..0..0
..1..0..1..0..1....0..0..0..0..0....1..0..1..0..0....1..0..0..0..0
..0..0..1..0..0....1..0..0..0..1....1..0..1..0..0....0..0..0..0..1
..1..0..0..1..0....0..1..0..0..1....1..0..1..0..0....1..0..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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