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A183683
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Number of (n+1) X 5 binary arrays with every 2 X 2 subblock nonsingular.
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1
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48, 208, 832, 3472, 14144, 58448, 239424, 986128, 4047680, 16650448, 68397888, 281218704, 1155579712, 4750209360, 19522035520, 80241997072, 329789811520, 1355498530256, 5571139502912, 22898117877648, 94112790021952
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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) = 13*a(n-2) + 16*a(n-3).
Empirical g.f.: 16*x*(3 + 13*x + 13*x^2) / (1 - 13*x^2 - 16*x^3). - Colin Barker, Apr 04 2018
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EXAMPLE
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Some solutions for 3 X 5:
..0..1..1..1..1....1..1..1..0..1....1..1..0..1..0....1..0..1..1..0
..1..1..0..1..0....1..0..1..1..0....0..1..1..0..1....0..1..0..1..1
..0..1..1..0..1....0..1..0..1..1....1..1..0..1..0....1..1..1..0..1
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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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