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A204279
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Number of (n+2) X 5 0..2 arrays with every 3 X 3 subblock having three equal elements in a row horizontally, vertically, diagonally or antidiagonally exactly three ways, and new values 0..2 introduced in row major order.
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1
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783, 865, 128, 256, 334, 778, 1990, 4758, 12782, 34702, 93502, 255070, 696478, 1900254, 5190878, 14181022, 38738206, 105833374, 289140766, 789937182, 2158145822, 5896161310, 16108592158, 44009486878, 120236148766, 328491227166
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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) = 3*a(n-1) -6*a(n-4) +4*a(n-6) for n>8.
Empirical g.f.: x*(783 - 1484*x - 2467*x^2 - 128*x^3 + 4264*x^4 + 4966*x^5 - 2708*x^6 - 3136*x^7) / ((1 - x)*(1 - 2*x - 2*x^2)*(1 - 2*x^3)). - Colin Barker, Jun 06 2018
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EXAMPLE
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Some solutions for n=4:
..0..0..0..0..0....0..1..0..2..1....0..1..0..2..2....0..0..0..0..0
..1..1..1..1..1....0..1..0..2..1....0..1..0..2..2....0..0..0..0..0
..0..0..0..0..0....0..1..0..2..1....0..1..0..2..2....1..1..1..1..1
..0..0..0..0..0....0..1..0..2..1....0..1..0..2..2....2..2..2..2..2
..1..1..1..1..1....0..1..0..2..1....0..1..0..2..2....0..0..0..0..0
..0..0..0..0..0....0..1..0..2..1....0..1..0..2..2....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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