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A207792
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Number of (n+1) X 2 0..3 arrays with every 2 X 3 or 3 X 2 subblock having an unequal number of clockwise and counterclockwise edge increases.
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1
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256, 2208, 20800, 184416, 1714176, 15376544, 141647296, 1279043040, 11724000896, 106260735008, 971279945280, 8821770053472, 80508174426368, 732094567369632, 6675191873895104, 60741010476989664, 553553902058209152
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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) + 61*a(n-2) + 83*a(n-3) + 272*a(n-4) + 336*a(n-5).
Empirical g.f.: 32*x*(8 + 61*x + 93*x^2 + 240*x^3 + 252*x^4) / (1 - x - 61*x^2 - 83*x^3 - 272*x^4 - 336*x^5). - Colin Barker, Jun 25 2018
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EXAMPLE
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Some solutions for n=4:
..2..0....3..0....1..0....3..3....0..1....2..0....2..1....2..0....1..0....1..3
..1..0....2..0....0..0....0..1....0..0....2..2....2..3....2..2....0..3....2..1
..0..0....3..1....1..2....2..3....1..2....1..3....0..1....1..0....0..1....2..0
..1..2....2..1....2..1....2..0....3..0....0..1....2..1....3..2....1..1....3..2
..1..1....3..2....0..1....1..1....1..1....2..2....0..2....3..0....2..3....3..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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