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A166762
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Number of nX3 1..3 arrays containing at least one of each value, and all equal values connected.
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0
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6, 174, 1548, 8100, 32208, 108456, 327042, 912330, 2403570, 6063738, 14792208, 35140296, 81722988, 186803940, 420988854, 937659294, 2067934782, 4522786278, 9821642100, 21198358092, 45510675048, 97254168192, 206980215882
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OFFSET
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1,1
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LINKS
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Table of n, a(n) for n=1..23.
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FORMULA
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Empirical: a(n) = 11*a(n-1) - 53*a(n-2) + 147*a(n-3) - 259*a(n-4) + 301*a(n-5) - 231*a(n-6) + 113*a(n-7) - 32*a(n-8) + 4*a(n-9).
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EXAMPLE
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Some solutions for n=4
...2.2.2...2.2.3...1.1.1...1.1.2...1.2.2...1.1.1...2.2.3...2.3.3...3.3.3
...1.1.2...3.2.3...3.1.1...2.2.2...3.3.2...1.3.3...2.3.3...2.3.1...3.1.1
...3.1.2...3.3.3...2.2.1...3.2.2...3.3.2...1.1.1...1.1.3...2.3.1...2.1.2
...3.1.1...3.1.3...1.1.1...3.3.3...2.2.2...2.2.1...1.1.1...2.1.1...2.2.2
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...1.1.2...2.2.2...1.1.1...1.1.1...3.3.3...3.3.3...2.2.2...3.3.1...2.1.3
...1.1.1...1.1.3...1.1.1...2.1.1...3.3.1...1.3.3...3.2.1...2.3.1...1.1.3
...1.3.3...3.3.3...2.3.1...2.1.3...2.3.3...1.1.3...3.3.1...2.3.3...1.1.1
...1.1.3...3.3.3...2.3.1...1.1.3...2.2.2...1.2.2...1.1.1...2.3.3...1.1.1
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CROSSREFS
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Sequence in context: A266311 A323820 A317795 * A323279 A214801 A233225
Adjacent sequences: A166759 A166760 A166761 * A166763 A166764 A166765
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KEYWORD
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nonn
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AUTHOR
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R. H. Hardin, Oct 21 2009
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STATUS
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approved
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