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A207734
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Number of 7Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 0 1 vertically
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1
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31, 961, 2449, 6241, 88243, 1247689, 4799749, 18464209, 184732327, 1848226081, 8873643337, 42603849649, 355158126283, 2960701807561, 16146759616669, 88059474768001, 662598445609375, 4985683837890625, 29297113012890625
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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) +48*a(n-3) +1512*a(n-4) +180*a(n-5) +612*a(n-6) -15840*a(n-7) -496179*a(n-8) -159489*a(n-9) +110160*a(n-10) +986580*a(n-11) +48988800*a(n-12) +17204400*a(n-13) +52488000*a(n-15) -1049760000*a(n-16)
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EXAMPLE
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Some solutions for n=4
..0..0..1..1....1..0..0..1....1..0..0..1....1..1..1..1....0..0..1..1
..0..1..1..1....1..1..0..1....1..0..0..1....0..0..1..1....0..1..1..1
..1..0..1..1....1..0..0..1....1..1..0..1....0..0..1..1....0..0..1..1
..0..0..1..1....1..0..0..1....1..0..0..1....1..0..1..1....1..0..1..1
..0..0..1..1....1..0..0..1....1..0..0..1....0..1..1..1....0..1..1..1
..1..0..1..1....1..1..0..1....1..0..0..1....0..0..1..1....0..0..1..1
..0..1..1..0....1..0..1..1....1..0..1..1....1..0..1..1....1..0..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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