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A204709
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Number of (n+1) X 5 0..1 arrays with the permanents of all 2 X 2 subblocks equal and nonzero.
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1
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49, 209, 833, 3473, 14145, 58449, 239425, 986129, 4047681, 16650449, 68397889, 281218705, 1155579713, 4750209361, 19522035521, 80241997073, 329789811521, 1355498530257, 5571139502913, 22898117877649, 94112790021953
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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) +13*a(n-2) +3*a(n-3) -16*a(n-4).
Empirical g.f.: x*(49 + 160*x - 13*x^2 - 224*x^3) / ((1 - x)*(1 - 13*x^2 - 16*x^3)). - Colin Barker, Jun 09 2018
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EXAMPLE
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Some solutions for n=4:
..1..1..0..1..0....1..0..1..1..1....1..1..1..0..1....1..0..1..0..1
..1..0..1..0..1....1..1..1..0..1....0..1..0..1..0....1..1..0..1..1
..0..1..0..1..1....1..0..1..1..1....1..1..1..0..1....1..0..1..0..1
..1..1..1..0..1....0..1..0..1..0....0..1..0..1..0....1..1..1..1..1
..1..0..1..1..0....1..0..1..1..1....1..1..1..0..1....0..1..0..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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