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%I #12 May 27 2016 04:16:15
%S 0,0,0,2016,23485,139417,583174,1954280,5607754,14335198,33495720,
%T 72817584,149172543,290727879,543010494
%N Number of nX2 1..7 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 increasing order.
%F Empirical: a(n) = ((2^5*4!)/(12)!)*binomial(n,4)*(n^8 + 78*n^7 + 3405*n^6 + 93498*n^5 + 1514529*n^4 + 12368202*n^3 + 25076435*n^2 - 107706168*n - 3335760). - _G. C. Greubel_, May 25 2016
%e Some solutions for n=4
%e ...1.2...1.1...1.2...3.7...2.3...2.5...1.5...1.2...1.4...1.2...2.3...2.7...1.2
%e ...3.6...2.4...6.4...4.2...5.1...3.6...4.2...1.5...2.6...1.4...4.1...3.5...3.7
%e ...3.7...3.7...6.5...5.2...6.4...4.1...4.3...6.4...5.3...5.6...6.5...3.6...5.7
%e ...4.5...6.5...7.3...6.1...7.4...4.7...7.6...7.3...5.7...7.3...7.7...4.1...6.4
%e ------
%e ...1.4...1.6...1.7...3.4...2.5...1.4...1.5...1.1...1.6...1.5...2.3...3.4...1.4
%e ...2.6...4.7...2.5...6.2...4.4...5.7...2.5...3.4...2.3...2.3...4.6...5.2...2.5
%e ...3.7...5.2...3.6...6.5...6.3...6.2...3.7...6.2...2.7...6.3...5.1...7.1...3.6
%e ...5.7...5.3...4.4...7.1...7.1...6.3...4.6...7.5...4.5...7.4...5.7...7.6...7.7
%K nonn,more
%O 1,4
%A _R. H. Hardin_, Oct 21 2009
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