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A166838
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Number of nX2 1..4 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 decreasing order.
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1
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0, 4, 49, 218, 662, 1626, 3479, 6748, 12156, 20664, 33517, 52294, 78962, 115934, 166131, 233048, 320824, 434316, 579177, 761938, 990094, 1272194, 1617935, 2038260, 2545460, 3153280, 3877029, 4733694, 5742058, 6922822, 8298731, 9894704
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OFFSET
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1,2
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LINKS
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R. H. Hardin, Table of n, a(n) for n=1..44
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FORMULA
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Empirical: a(n)=(n^6+18*n^5+100*n^4-30*n^3-551*n^2+462*n)/180
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EXAMPLE
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All solutions for n=3
...1.1...1.1...1.1...1.1...1.1...1.1...1.1...1.1...1.1...2.1...2.1...2.1...2.1
...2.1...2.1...2.2...3.1...3.2...3.2...3.2...3.3...4.2...2.1...2.1...2.2...2.2
...3.4...4.3...4.3...4.2...3.4...4.2...4.4...4.2...4.3...3.4...4.3...3.4...4.3
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...2.1...2.1...2.1...2.1...2.1...2.1...2.1...2.1...2.1...2.1...2.1...2.1...2.1
...2.3...2.3...2.3...2.4...2.4...3.1...3.1...3.1...3.3...3.3...3.3...3.4...3.4
...2.4...4.3...4.4...3.3...3.4...3.4...4.1...4.4...3.4...4.3...4.4...3.4...4.4
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...2.1...2.1...2.1...2.2...2.2...2.2...2.2...2.2...2.2...3.1...3.1...3.1...3.1
...4.1...4.3...4.3...3.1...3.1...3.1...3.2...3.3...4.1...3.1...3.2...3.2...3.2
...4.3...4.3...4.4...3.4...4.1...4.4...4.1...4.1...4.3...4.2...3.4...4.2...4.4
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...3.1...3.1...3.1...3.1...3.2...3.2...3.2...3.2...3.3...4.1
...3.3...4.1...4.2...4.2...3.2...3.3...4.1...4.1...4.1...4.2
...4.2...4.2...4.2...4.4...4.1...4.1...4.1...4.4...4.2...4.3
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CROSSREFS
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Sequence in context: A016874 A092866 A041065 * A166826 A078187 A100256
Adjacent sequences: A166835 A166836 A166837 * A166839 A166840 A166841
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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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