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A231524
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Number of 2 X n 0..1 arrays with no element less than a strict majority of its horizontal, diagonal and antidiagonal neighbors.
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1
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4, 10, 34, 107, 342, 1069, 3381, 10689, 33808, 106804, 337525, 1066772, 3371763, 10656541, 33680325, 106448622, 336438736, 1063336915, 3360744286, 10621851017, 33571065345, 106103576857, 335347363656, 1059887498352, 3349844553061
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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) = 4*a(n-1) - 3*a(n-2) + a(n-3) + 6*a(n-4) - 18*a(n-5).
Empirical g.f.: x*(4 - 6*x + 6*x^2 - 3*x^3 - 18*x^4) / (1 - 4*x + 3*x^2 - x^3 - 6*x^4 + 18*x^5). - Colin Barker, Sep 29 2018
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EXAMPLE
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Some solutions for n=7:
0 1 0 0 0 0 1 1 0 0 0 0 0 1 0 0 0 1 0 0 0
1 0 0 1 0 1 1 1 0 0 1 0 0 1 0 0 1 0 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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