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A204624
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Number of (n+1) X 3 0..2 arrays with every 2 X 2 subblock having unequal diagonal elements or unequal antidiagonal elements, and new values 0..2 introduced in row major order.
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1
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96, 2049, 43734, 933462, 19923888, 425257068, 9076721064, 193734264456, 4135079723136, 88259474206608, 1883817316421472, 40208348322379872, 858210220662456576, 18317707978060726464, 390974632428061590144
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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) = 22*a(n-1) -14*a(n-2).
G.f.: 3*x*(32 - 21*x) / (1 - 22*x + 14*x^2).
a(n) = (3*(11+sqrt(107))^n*(31+3*sqrt(107)) + (11-sqrt(107))^n*(-93+9*sqrt(107))) / (4*sqrt(107)).
(End)
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EXAMPLE
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Some solutions for n=3:
..0..0..0....0..0..1....0..0..1....0..1..2....0..0..1....0..0..1....0..1..0
..0..1..1....2..0..2....2..0..2....1..2..2....2..0..0....2..0..2....2..1..2
..1..2..0....0..0..2....2..2..1....0..2..1....2..0..1....1..0..2....2..1..1
..1..2..1....2..0..2....0..2..1....1..1..0....2..2..2....1..2..1....0..1..2
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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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