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 A166838 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. 1
 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS R. H. Hardin, Table of n, a(n) for n=1..44 FORMULA Empirical: a(n)=(n^6+18*n^5+100*n^4-30*n^3-551*n^2+462*n)/180 EXAMPLE 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 ------ ...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 ------ ...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 ------ ...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 CROSSREFS Sequence in context: A016874 A092866 A041065 * A166826 A078187 A100256 Adjacent sequences:  A166835 A166836 A166837 * A166839 A166840 A166841 KEYWORD nonn AUTHOR R. H. Hardin Oct 21 2009 STATUS approved

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