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%I #7 May 27 2016 02:53:23
%S 0,0,160,1245,5326,16876,44382,102609,215668,421056,774852,1358269,
%T 2285778,3715036,5858866,8999553,13505736,19852192,28642824,40637181,
%U 56780854,78240108,106441126,143114257,190343676,250622880
%N Number of nX2 1..5 arrays containing at least one of each value, all equal values connected, and rows considered as a single number in nondecreasing order.
%F Empirical: a(n) = (1/2520)*(n-1)*(n-2)*(n^6 + 35*n^5 + 551*n^4 + 4033*n^3 + 8106*n^2 -11790*n + 1260).
%F From _G. C. Greubel_, May 26 2016: (Start)
%F Empirical G.f.: x^3*(x^6 + 33*x^5 - 186*x^4 + 322*x^3 - 119*x^2 - 195*x + 160) ) /(1-x)^9.
%F Empirical E.g.f.: (1/2520)*(2520 - 2520*x + 1260*x^2 + 66780*x^3 + 63630*x^4 + 14700*x^5 + 1386*x^6 + 60*x^7 + x^8)*exp(x) - 1. (End)
%e Some solutions for n=4
%e ...1.3...1.3...3.2...1.1...2.1...2.1...2.1...1.3...2.2...1.3...3.1...4.2...1.3
%e ...2.3...1.4...4.1...3.3...2.4...2.3...2.4...2.5...2.4...2.3...3.3...4.3...1.3
%e ...2.3...2.5...4.4...4.4...5.3...3.3...3.3...4.5...3.1...5.4...4.3...5.1...2.5
%e ...5.4...2.5...5.5...5.2...5.3...5.4...5.5...5.5...5.5...5.5...5.2...5.1...4.4
%e ------
%e ...2.2...1.1...1.1...2.2...1.1...1.1...1.1...1.3...1.1...2.1...2.3...1.3...1.1
%e ...4.4...2.4...2.5...2.4...1.2...3.1...1.1...2.4...1.2...3.3...4.4...1.3...4.2
%e ...5.1...3.4...3.3...3.4...4.4...3.5...2.5...4.4...1.4...3.4...5.1...2.4...5.3
%e ...5.3...3.5...4.4...5.1...5.3...4.2...3.4...5.4...3.5...3.5...5.1...5.5...5.3
%K nonn
%O 1,3
%A _R. H. Hardin_, Oct 21 2009
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