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A235948
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Number of (n+1) X (2+1) 0..2 arrays colored with the upper median value of each 2 X 2 subblock.
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1
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294, 722, 1372, 2660, 5034, 9752, 18468, 35794, 67924, 131474, 251786, 485354, 926434, 1789970, 3433586, 6602990, 12649018, 24390182, 46809866, 89947622, 172622482, 332388566, 638104130, 1225937510, 2354814226, 4530138566
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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) = 3*a(n-3) + 10*a(n-4) - 12*a(n-7) - 6*a(n-8) for n>12.
Empirical g.f.: 2*x*(147 + 361*x + 686*x^2 + 889*x^3 - 36*x^4 - 792*x^5 - 1616*x^6 - 1190*x^7 - 622*x^8 - 327*x^9 - 62*x^10 + 5*x^11) / (1 - 3*x^3 - 10*x^4 + 12*x^7 + 6*x^8). - Colin Barker, Oct 20 2018
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EXAMPLE
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Some solutions for n=5:
..0..2..1....1..0..0....1..0..0....2..0..1....1..2..2....2..2..1....1..2..1
..2..1..0....2..1..0....1..0..1....1..2..0....0..0..2....0..0..0....2..1..0
..0..0..0....1..2..0....0..0..2....0..1..2....1..0..1....2..1..0....0..0..0
..0..1..2....0..0..0....2..1..2....0..0..0....2..0..0....1..2..1....0..1..2
..1..2..1....0..2..1....2..0..0....2..1..0....2..1..2....0..0..2....0..2..1
..2..1..0....1..0..2....1..1..0....2..1..0....1..0..2....0..1..0....2..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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