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A207120
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Number of nX5 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 0 1 and 0 1 1 vertically
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1
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14, 196, 896, 4096, 12288, 36864, 87744, 208849, 428666, 879844, 1628368, 3013696, 5166336, 8856576, 14311584, 23126481, 35653926, 54967396, 81554000, 121000000, 173888000, 249892864, 349562304, 488984769, 668387538, 913611076, 1224032096
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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) = 2*a(n-1) +8*a(n-2) -18*a(n-3) -27*a(n-4) +72*a(n-5) +48*a(n-6) -168*a(n-7) -42*a(n-8) +252*a(n-9) -252*a(n-11) +42*a(n-12) +168*a(n-13) -48*a(n-14) -72*a(n-15) +27*a(n-16) +18*a(n-17) -8*a(n-18) -2*a(n-19) +a(n-20)
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EXAMPLE
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Some solutions for n=4
..0..1..1..0..0....0..0..0..0..0....1..0..0..0..0....0..1..1..0..0
..1..1..1..1..1....1..0..1..1..0....1..0..1..1..1....1..0..1..1..1
..0..0..0..0..0....0..0..0..0..0....0..0..0..0..0....0..1..1..0..0
..0..1..1..0..0....1..0..0..0..0....0..0..0..0..0....0..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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