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%I #8 May 27 2016 03:01:49
%S 0,12,116,487,1438,3472,7342,14119,25268,42732,69024,107327,161602,
%T 236704,338506,474031,651592,880940,1173420,1542135,2002118,2570512,
%U 3266758,4112791,5133244,6355660,7810712,9532431,11558442,13930208
%N Number of nX2 1..4 arrays containing at least one of each value, all equal values connected, and rows considered as a single number in nondecreasing order.
%H R. H. Hardin, <a href="/A166777/b166777.txt">Table of n, a(n) for n=1..45</a>
%F Empirical: a(n) = (2*n^6 + 36*n^5 + 215*n^4 + 60*n^3 - 1297*n^2 + 1164*n - 180)/180.
%F From _G. C. Greubel_, May 26 2016: (Start)
%F Empirical G.f.: -x^2*(x-2)*(x^4 + 9*x^3 - 27*x^2 + 19*x + 6)/(1-x)^7.
%F Empirical E.g.f.: (1/180)*(-180 + 180*x + 990*x^2 + 2430*x^3 + 705*x^4 + 66*x^5 + 2*x^6)*exp(x) + 1. (End)
%e Some solutions for n=4
%e ...1.1...1.3...1.1...2.1...3.2...2.1...1.2...3.1...1.2...1.1...1.1...1.1...2.1
%e ...2.2...1.4...1.2...3.4...3.2...2.4...1.2...3.2...1.3...1.2...2.1...3.2...3.1
%e ...3.3...2.4...3.3...3.4...3.3...3.3...1.3...3.2...4.4...3.4...3.3...3.2...4.4
%e ...4.4...4.4...4.3...3.4...4.1...3.3...1.4...3.4...4.4...4.4...4.4...4.4...4.4
%e ------
%e ...1.1...2.3...1.2...2.2...3.1...1.1...1.1...1.1...2.1...1.1...2.2...1.2...2.1
%e ...2.1...2.3...2.2...2.2...3.2...1.1...4.2...3.3...2.1...2.1...3.2...3.2...3.1
%e ...2.1...4.1...3.3...3.1...4.2...3.2...4.2...3.3...3.3...4.1...3.3...3.4...3.3
%e ...4.3...4.4...3.4...4.4...4.2...4.2...4.3...4.2...3.4...4.3...4.1...4.4...3.4
%K nonn
%O 1,2
%A _R. H. Hardin_, Oct 21 2009
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