|
%I #7 May 27 2016 03:01:19
%S 4,17,44,91,164,269,412,599,836,1129,1484,1907,2404,2981,3644,4399,
%T 5252,6209,7276,8459,9764,11197,12764,14471,16324,18329,20492,22819,
%U 25316,27989,30844,33887,37124,40561,44204,48059,52132,56429,60956,65719,70724
%N Number of nX3 1..2 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) = n^3 + n^2 + 3*n - 1.
%F From _G. C. Greubel_, May 26 2016: (Start)
%F Empirical G.f.: x*(x^3 + x + 4)/(1-x)^4.
%F Empirical E.g.f.: (-1 + 5*x + 4*x^2 + x^3)*exp(x) + 1. (End)
%e Some solutions for n=4
%e ...1.1.2...1.1.1...1.1.1...1.1.1...2.2.1...1.1.1...1.1.1...1.1.2...1.1.1
%e ...1.1.2...2.1.2...1.1.2...1.1.1...2.2.1...1.1.1...1.2.1...2.1.2...2.2.1
%e ...1.2.2...2.2.2...2.2.2...1.1.2...2.2.1...1.2.1...1.2.2...2.1.2...2.2.1
%e ...2.2.2...2.2.2...2.2.2...1.1.2...2.2.2...1.2.1...2.2.2...2.2.2...2.2.2
%e ------
%e ...1.1.1...1.2.2...1.1.1...1.2.2...2.1.1...1.1.1...2.2.1...2.1.2...1.1.1
%e ...1.1.1...2.2.2...1.1.2...1.2.2...2.2.1...1.1.1...2.2.1...2.1.2...1.1.1
%e ...1.1.1...2.2.2...1.1.2...1.2.2...2.2.1...1.1.2...2.2.2...2.1.2...1.1.1
%e ...2.2.1...2.2.2...2.2.2...1.2.2...2.2.2...1.2.2...2.2.2...2.2.2...2.1.1
%K nonn
%O 1,1
%A _R. H. Hardin_, Oct 21 2009
| 