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A239813
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Number of nX2 0..3 arrays with no element equal to zero plus the sum of elements to its left or one plus the sum of elements above it, modulo 4
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1
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4, 23, 113, 582, 2981, 15266, 78188, 400542, 2051667, 10509067, 53831920, 275740995, 1412438656, 7234951864, 37059718148, 189831642853, 972377820507, 4980827553280, 25513377870835, 130687610786192, 669423377137934
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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) = a(n-1) +16*a(n-2) +31*a(n-3) -8*a(n-4) -78*a(n-5) -45*a(n-6) +56*a(n-7) -32*a(n-8) +32*a(n-9) +16*a(n-10)
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EXAMPLE
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Some solutions for n=5
..2..0....2..0....2..0....3..2....3..2....3..0....3..0....3..2....2..3....2..0
..1..3....2..3....2..3....3..2....3..2....1..2....2..0....1..0....2..3....1..0
..3..2....3..1....3..1....2..3....1..0....2..0....1..3....3..2....2..0....3..0
..1..3....1..0....3..2....3..2....1..2....1..2....1..2....3..2....1..2....1..3
..2..3....3..0....1..2....1..3....2..0....1..0....1..3....2..1....2..0....1..3
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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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