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A188987
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Number of n X 4 binary arrays without the pattern 0 0 1 antidiagonally or horizontally.
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1
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12, 144, 1256, 10812, 92532, 791388, 6768028, 57879084, 494973804, 4232940812, 36199474380, 309572453388, 2647417026444, 22640311889164, 193616539257612, 1655779498747404, 14159977029956108, 121093992068450316
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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) = 9*a(n-1) -36*a(n-3) +24*a(n-4) +36*a(n-5) -48*a(n-6) +16*a(n-7).
Empirical g.f.: 4*x*(1 + x - 2*x^2 + x^3)*(3 + 6*x - 10*x^2 + 4*x^3) / ((1 - x)*(1 - 8*x - 8*x^2 + 28*x^3 + 4*x^4 - 32*x^5 + 16*x^6)). - Colin Barker, May 01 2018
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EXAMPLE
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Some solutions for 3 X 4:
..1..0..1..1....1..1..0..0....1..0..1..1....1..0..1..1....1..0..1..1
..1..1..1..0....1..1..1..0....1..0..0..0....0..1..0..0....1..1..0..1
..0..1..1..0....0..1..0..1....1..0..0..0....1..1..0..0....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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