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 A166776 Number of nX2 1..3 arrays containing at least one of each value, all equal values connected, and rows considered as a single number in nondecreasing order. 1
 0, 12, 51, 135, 286, 530, 897, 1421, 2140, 3096, 4335, 5907, 7866, 10270, 13181, 16665, 20792, 25636, 31275, 37791, 45270, 53802, 63481, 74405, 86676, 100400, 115687, 132651, 151410, 172086, 194805, 219697, 246896, 276540, 308771, 343735, 381582 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS R. H. Hardin, Table of n, a(n) for n=1..83 FORMULA Empirical: a(n) = (n^4 + 8*n^3 + 8*n^2 - 23*n + 6)/6. From G. C. Greubel, May 26 2016: (Start) Empirical G.f.: x^2*(x^3 - 9*x + 12)/(1-x)^5. Empirical E.g.f.: (1/6)*(6 - 6*x + 39*x^2 + 14*x^3 + x^4)*exp(x) - 1. (End) EXAMPLE All solutions for n=3 ...2.2...2.2...2.2...2.1...2.1...2.1...2.1...2.1...2.1...2.1...2.1...2.1...2.1 ...2.2...3.1...3.1...2.2...2.2...2.2...2.1...2.1...2.1...2.3...2.3...3.1...3.1 ...3.1...3.1...3.3...2.3...3.2...3.3...2.3...3.1...3.3...2.3...3.3...3.1...3.3 ------ ...2.1...1.2...1.2...1.2...1.2...1.2...1.2...1.2...1.2...1.2...1.2...1.2...1.1 ...3.3...2.2...2.2...2.2...1.2...1.2...1.2...1.3...1.3...3.2...3.2...3.3...2.2 ...3.3...2.3...3.2...3.3...1.3...3.2...3.3...1.3...3.3...3.2...3.3...3.3...2.3 ------ ...1.1...1.1...1.1...1.1...1.1...1.1...1.1...1.1...1.1...1.1...1.1...1.1...1.1 ...2.2...2.2...2.1...2.1...2.1...2.3...2.3...1.2...1.2...1.2...1.1...1.1...1.3 ...3.2...3.3...2.3...3.1...3.3...2.3...3.3...1.3...3.2...3.3...2.3...3.2...2.2 ------ ...1.1...1.1...1.1...1.1...1.3...1.3...1.3...1.3...1.3...3.1...3.1...3.1 ...1.3...3.2...3.2...3.1...2.2...2.3...2.3...1.3...1.3...3.2...3.2...3.1 ...2.3...3.2...3.3...3.2...2.2...2.3...3.3...2.2...2.3...3.2...3.3...3.2 CROSSREFS Sequence in context: A145886 A349860 A268351 * A200887 A236770 A334695 Adjacent sequences: A166773 A166774 A166775 * A166777 A166778 A166779 KEYWORD nonn AUTHOR R. H. Hardin, Oct 21 2009 STATUS approved

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Last modified June 5 19:44 EDT 2023. Contains 363138 sequences. (Running on oeis4.)