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A221023
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Equals one maps: number of n X 5 binary arrays indicating the locations of corresponding elements equal to exactly one of their horizontal, vertical and antidiagonal neighbors in a random 0..3 n X 5 array.
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1
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16, 726, 30167, 1038208, 33512960, 1073575936, 34359074816, 1099508973568, 35184361472000, 1125899864375296, 36028796849094656, 1152921503927369728, 36893488144701194240, 1180591620706539667456, 37778931862913675165696
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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) = 36*a(n-1) - 128*a(n-2) for n>5.
Empirical g.f.: x*(16 + 150*x + 6079*x^2 + 45124*x^3 - 1152*x^4) / ((1 - 4*x)*(1 - 32*x)). - Colin Barker, Aug 03 2018
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EXAMPLE
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Some solutions for n=3:
..1..0..0..0..1....1..0..0..1..0....0..1..1..0..1....1..0..1..0..0
..0..1..1..0..0....1..0..0..0..1....1..0..1..1..0....0..0..1..0..1
..0..1..0..1..0....1..1..1..1..0....0..1..1..0..0....1..0..1..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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