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A185883
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1/729 the number of (n+2) X 3 0..2 arrays with no 3 X 3 subblock trace equal to any horizontal or vertical neighbor 3 X 3 subblock trace.
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1
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27, 588, 12900, 282672, 6195480, 135783240, 2975926392, 65222436072, 1429460497272, 31329049201704, 686629243183416, 15048644047773288, 329816550981847032, 7228488945306025128, 158424591792311309496
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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) = 10*a(n-1) + 221*a(n-2) + 846*a(n-3) + 756*a(n-4).
Empirical g.f.: 3*x*(9 + 106*x + 351*x^2 + 294*x^3) / (1 - 10*x - 221*x^2 - 846*x^3 - 756*x^4). - Colin Barker, Apr 17 2018
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EXAMPLE
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Some solutions for 4 X 3:
..0..1..1....0..1..1....0..0..1....0..0..1....0..0..0....0..0..1....0..1..1
..0..1..0....1..1..1....1..2..0....1..0..0....1..1..1....0..0..1....1..0..0
..0..0..1....0..2..0....0..2..0....1..0..0....2..2..1....2..2..2....1..0..1
..1..2..1....1..0..2....0..0..2....0..2..1....0..0..1....2..1..2....0..1..1
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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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