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A205164
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Number of (n+1) X 3 0..3 arrays with every 2 X 2 subblock having unequal diagonal elements or unequal antidiagonal elements, and new values 0..3 introduced in row major order.
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1
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159, 8479, 474853, 26702419, 1502057181, 84495589507, 4753161432989, 267381383420963, 15041106058843389, 846113027177563139, 47596716094317460573, 2677476070233122179939, 150617073927319718240061
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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) = 62*a(n-1) -329*a(n-2) +324*a(n-3) -84*a(n-4).
Empirical g.f.: x*(159 - 1379*x + 1466*x^2 - 392*x^3) / ((1 - 5*x + 2*x^2)*(1 - 57*x + 42*x^2)). - Colin Barker, Jun 11 2018
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EXAMPLE
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Some solutions for n=4:
..0..1..0....0..1..1....0..0..0....0..0..0....0..0..0....0..0..1....0..0..0
..0..1..0....0..2..1....0..1..1....0..1..0....0..1..1....0..1..1....0..1..1
..0..1..0....1..1..0....2..0..2....2..2..1....1..1..0....2..2..1....2..3..2
..0..1..1....3..2..3....2..1..0....1..3..2....0..0..2....0..3..1....3..1..1
..0..0..0....3..0..0....3..2..2....0..1..0....0..1..2....0..1..0....1..0..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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