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%I #10 May 27 2016 03:13:52
%S 0,8,67,269,776,1846,3863,7371,13112,22068,35507,55033,82640,120770,
%T 172375,240983,330768,446624,594243,780197,1012024,1298318,1648823,
%U 2074531,2587784,3202380,3933683,4798737,5816384,7007386,8394551
%N 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 nondecreasing order.
%H R. H. Hardin, <a href="/A166797/b166797.txt">Table of n, a(n) for n=1..44</a>
%F Empirical: a(n) = (n^6 + 18*n^5 + 115*n^4 + 90*n^3 - 746*n^2 + 702*n - 180) /180.
%F From _G. C. Greubel_, May 26 2016: (Start)
%F Empirical G.f.: -x^2*(x^5 + 2*x^4 - 20*x^3 + 32*x^2 - 11*x - 8)/(1-x)^7.
%F Empirical E.g.f.: (1/180)*(-180 + 180*x + 630*x^2 + 1320*x^3 + 360*x^4 + 33*x^5 + x^6)*exp(x) + 1. (End)
%e Some solutions for n=4
%e ...1.4...1.2...1.4...1.2...1.2...1.4...1.4...2.3...1.3...1.1...1.2...1.2...1.1
%e ...1.4...3.3...1.4...2.2...2.2...2.4...1.4...3.3...1.3...1.4...3.2...1.2...1.2
%e ...3.2...3.3...2.2...2.2...3.2...3.3...2.3...3.3...2.2...2.2...4.4...3.3...1.2
%e ...3.2...3.4...2.3...3.4...4.4...3.3...3.3...4.1...2.4...3.3...4.4...4.4...3.4
%e ------
%e ...1.2...1.2...1.2...1.4...1.2...1.1...1.3...1.3...1.3...1.4...1.2...1.2...1.3
%e ...3.2...3.3...1.3...2.2...3.3...1.4...2.2...1.3...2.3...2.4...3.2...3.2...2.4
%e ...4.2...4.3...3.3...3.2...4.4...3.2...2.4...1.3...3.3...2.4...3.3...4.2...2.4
%e ...4.4...4.3...4.4...3.2...4.4...3.3...4.4...4.2...4.4...3.3...4.4...4.2...4.4
%K nonn
%O 1,2
%A _R. H. Hardin_, Oct 21 2009
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