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A166819
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Number of nX3 1..3 arrays containing at least one of each value, all equal values connected, rows considered as a single number in nondecreasing order, and columns considered as a single number in increasing order.
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0
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1, 14, 83, 308, 877, 2106, 4487, 8744, 15897, 27334, 44891, 70940, 108485, 161266, 233871, 331856, 461873, 631806, 850915, 1129988, 1481501
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OFFSET
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1,2
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LINKS
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FORMULA
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Empirical: a(n)=(n^6+9*n^5+55*n^4+15*n^3-56*n^2+66*n)/90
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EXAMPLE
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Some solutions for n=4
...1.1.1...1.1.1...1.1.1...1.3.3...1.2.2...1.1.3...1.1.1...1.1.3...1.1.1
...1.2.2...1.1.2...1.2.3...2.2.3...2.2.3...1.1.3...1.1.2...1.2.2...1.1.2
...2.2.3...1.2.2...1.2.3...2.3.3...2.2.3...2.2.3...1.2.2...2.2.2...1.3.2
...3.3.3...3.3.2...2.2.3...3.3.3...2.2.3...2.3.3...1.3.2...2.2.2...1.3.2
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...1.2.3...1.1.1...1.2.2...1.1.3...1.2.3...1.1.2...1.1.1...1.1.1...1.1.2
...1.2.3...1.1.3...1.2.2...1.2.3...1.2.3...2.2.2...1.2.3...1.2.2...1.2.2
...1.2.3...2.2.3...1.2.2...1.3.3...1.3.3...2.3.2...1.2.3...1.2.3...1.3.2
...2.2.3...2.3.3...2.2.3...1.3.3...1.3.3...3.3.3...3.3.3...3.3.3...3.3.2
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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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