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

%S 225,11786,265155,4434848,63388030

%N Number of nX6 1..4 arrays with all 1s connected, all 2s connected, all 3s connected, all 4s connected, 1 in the upper left corner, 2 in the upper right corner, 3 in the lower left corner, 4 in the lower right corner, and with no element having more than 3 neighbors with the same value

%e Some solutions for n=3

%e ...1.1.2.2.2.2...1.1.2.2.2.2...1.1.1.2.2.2...1.1.1.2.2.2...1.1.2.2.2.2

%e ...3.3.3.2.2.2...1.1.3.2.2.2...1.1.1.2.4.2...3.3.3.2.4.4...1.1.1.2.2.2

%e ...3.3.3.3.4.4...3.3.3.4.4.4...3.3.3.3.4.4...3.3.3.4.4.4...3.3.3.4.4.4

%e ------

%e ...1.1.2.2.2.2...1.1.2.2.2.2...1.1.2.2.2.2...1.1.1.2.2.2...1.1.1.2.2.2

%e ...3.1.3.2.2.4...1.1.1.4.4.4...3.3.3.4.4.4...3.1.3.4.2.4...1.1.3.2.2.4

%e ...3.3.3.3.4.4...3.3.4.4.4.4...3.3.3.3.4.4...3.3.3.4.4.4...3.3.3.3.4.4

%K nonn

%O 2,1

%A _R. H. Hardin_ Aug 24 2009