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A232043
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Number of n X 4 0..1 arrays with no element less than a strict majority of its horizontal and antidiagonal neighbors.
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1
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7, 34, 318, 3082, 29974, 290672, 2821630, 27382537, 265752221, 2579134666, 25030650682, 242923857095, 2357589444796, 22880536455569, 222056873956095, 2155074272108794, 20915115264627031, 202982352989424279
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OFFSET
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1,1
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LINKS
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FORMULA
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Empirical: a(n) = 7*a(n-1) + 29*a(n-2) - 15*a(n-3) - 116*a(n-4) + 17*a(n-5) + 99*a(n-6) + 12*a(n-7) - 16*a(n-8) for n>9.
Empirical g.f.: x*(7 - 15*x - 123*x^2 - 25*x^3 + 500*x^4 + 71*x^5 - 473*x^6 - 95*x^7 + 84*x^8) / (1 - 7*x - 29*x^2 + 15*x^3 + 116*x^4 - 17*x^5 - 99*x^6 - 12*x^7 + 16*x^8). - Colin Barker, Oct 02 2018
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EXAMPLE
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Some solutions for n=6:
..0..0..0..0....0..0..1..0....0..0..0..0....0..0..0..1....0..0..0..1
..0..1..0..1....0..0..0..0....0..1..1..0....0..0..0..1....0..0..0..1
..0..0..1..0....0..1..0..1....0..0..0..1....1..0..0..1....0..0..0..0
..0..0..0..0....1..0..0..0....0..1..1..0....0..0..0..0....0..0..0..0
..1..0..1..1....0..0..0..0....0..0..0..0....0..0..1..0....1..1..0..0
..0..0..0..0....1..1..0..0....1..1..1..1....1..1..0..0....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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