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Number of nX2 1..5 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.
0

%I #3 Mar 31 2012 12:35:36

%S 0,0,105,767,3159,9751,25148,57258,118866,229698,419067,729201,

%T 1219361,1970865,3093142,4730948,7072884,10361364,14904189,21087891,

%U 29393019,40411547,54866592,73634638,97770470,128535030

%N Number of nX2 1..5 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)=(n^8+32*n^7+476*n^6+3038*n^5-1351*n^4-33082*n^3+46234*n^2-15348*n)/5040

%e Some solutions for n=4

%e ...1.3...1.4...1.3...1.1...1.5...1.3...1.1...2.4...1.2...1.2...1.3...1.4...1.3

%e ...2.3...3.2...2.2...1.3...2.3...2.5...2.3...2.4...3.4...3.2...2.2...1.4...1.3

%e ...4.4...3.2...2.2...2.4...4.4...4.4...3.3...2.5...5.4...4.2...4.5...2.4...2.3

%e ...5.4...3.5...5.4...5.4...4.4...4.4...4.5...3.1...5.4...5.2...5.5...5.3...4.5

%e ------

%e ...2.5...1.5...2.3...1.2...1.2...1.3...1.5...1.4...1.3...2.5...1.5...1.3...1.4

%e ...3.1...2.3...4.4...4.4...1.4...1.4...2.5...3.4...2.3...3.3...2.2...2.3...1.5

%e ...3.4...3.3...5.1...5.3...1.4...4.4...4.3...4.4...4.3...4.1...2.2...3.3...2.2

%e ...3.4...3.4...5.1...5.3...5.3...5.2...4.3...5.2...5.5...4.1...3.4...5.4...2.3

%K nonn

%O 1,3

%A _R. H. Hardin_ Oct 21 2009