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A206131
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Number of (n+1) X 3 0..3 arrays with every 2 X 3 or 3 X 2 subblock having exactly three counterclockwise and three clockwise edge increases.
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1
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564, 6668, 91924, 1269044, 17521788, 241927532, 3340355572, 46121153588, 636806710044, 8792555155244, 121401086008468, 1676216233423412, 23143951620064572, 319554533544992108, 4412172198832106164
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OFFSET
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1,1
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COMMENTS
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Column 2 of A206137.
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LINKS
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R. H. Hardin, Table of n, a(n) for n = 1..210
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FORMULA
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Empirical: a(n) = 17*a(n-1) - 47*a(n-2) + 41*a(n-3) - 10*a(n-4) for n > 5.
Empirical g.f.: 4*x*(3 - 5*x)*(47 - 165*x + 148*x^2 - 36*x^3) / ((1 - x)*(1 - 16*x + 31*x^2 - 10*x^3)). - Colin Barker, Jun 13 2018
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EXAMPLE
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Some solutions for n=4:
1 0 1 0 2 1 1 2 1 3 1 3 0 2 3 0 3 2 2 1 2
0 1 2 3 0 2 3 0 3 0 3 2 1 3 2 1 0 3 3 2 3
3 0 1 0 1 0 0 2 1 1 0 3 3 2 0 2 1 0 0 3 0
0 1 3 3 0 3 3 0 2 3 1 0 2 3 1 3 2 1 2 1 2
2 3 1 0 1 0 2 3 0 2 0 3 1 2 3 0 3 2 3 2 1
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CROSSREFS
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Cf. A206137.
Sequence in context: A252293 A252286 A252285 * A283782 A203781 A189352
Adjacent sequences: A206128 A206129 A206130 * A206132 A206133 A206134
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KEYWORD
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nonn
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AUTHOR
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R. H. Hardin, Feb 04 2012
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STATUS
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approved
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