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A184756
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Half the number of n X 4 binary arrays with no 1 having an adjacent 1 both above and to its left.
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2
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8, 89, 1056, 12397, 145778, 1713803, 20148584, 236878817, 2784890782, 32740859687, 384921344068, 4525368067837, 53202963328218, 625486206737315, 7353594054643744, 86453298151112665, 1016397248157274582
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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) + 39*a(n-2) + 58*a(n-3) + 32*a(n-4).
Empirical g.f.: x*(8 + 25*x + 32*x^2 + 14*x^3) / (1 - 8*x - 39*x^2 - 58*x^3 - 32*x^4). - Colin Barker, Feb 27 2018
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EXAMPLE
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Some solutions for 3 X 4:
..1..1..0..0....0..1..1..1....1..0..1..0....0..1..1..0....0..1..0..1
..1..0..0..1....0..0..0..0....0..1..0..0....1..0..0..1....0..1..0..0
..1..1..1..0....0..0..0..1....0..0..0..1....1..1..0..0....0..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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