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A206754
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Number of (n+1) X 2 0..2 arrays with every 2 X 3 or 3 X 2 subblock having no more than three equal edges, and new values 0..2 introduced in row major order.
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1
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14, 106, 861, 7010, 56970, 463064, 3764188, 30597928, 248720792, 2021775088, 16434387520, 133590069408, 1085912510000, 8827048192048, 71752354780224, 583252782273232, 4741082144156272, 38538795836723584, 313269996043880464
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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) = 7*a(n-1) + 5*a(n-2) + 34*a(n-3) - 2*a(n-4) + 12*a(n-5) for n>6.
Empirical g.f.: x*(14 + 8*x + 49*x^2 - 23*x^3 + 19*x^4 - 6*x^5) / (1 - 7*x - 5*x^2 - 34*x^3 + 2*x^4 - 12*x^5). - Colin Barker, Jun 17 2018
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EXAMPLE
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Some solutions for n=4:
..0..0....0..1....0..0....0..0....0..0....0..1....0..1....0..0....0..0....0..1
..0..0....0..2....1..2....0..1....0..0....2..2....2..0....0..0....0..0....0..0
..1..2....1..2....1..2....2..0....1..2....2..1....1..2....1..2....1..2....2..0
..1..0....2..1....1..0....2..2....1..1....2..0....2..0....2..2....2..2....0..2
..1..2....1..0....1..0....0..2....2..2....1..1....0..1....1..2....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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