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%I #4 Dec 18 2015 18:17:24
%S 1,80,739,3496,13654
%N Number of n X n 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 2 neighbors with the same value
%e Some solutions for n=4
%e ...1.1.1.2...1.2.2.2...1.1.1.2...1.1.2.2...1.3.2.2...1.1.1.2...1.1.2.2
%e ...1.4.4.2...1.1.4.4...1.2.2.2...3.1.2.4...1.3.2.4...1.2.2.2...3.1.4.2
%e ...1.3.4.2...3.1.1.4...1.1.3.3...3.1.1.4...3.3.2.4...1.3.3.3...3.1.4.2
%e ...3.3.4.4...3.3.3.4...3.3.3.4...3.3.3.4...3.4.4.4...3.3.4.4...3.1.4.4
%e ------
%e ...1.2.2.2...1.1.1.2...1.2.2.2...1.1.2.2...1.3.2.2...1.1.2.2...1.4.2.2
%e ...1.1.1.4...1.3.1.2...1.4.4.4...1.2.2.3...1.3.4.2...1.4.4.2...3.4.2.2
%e ...3.4.1.4...3.3.1.1...1.1.1.4...2.2.3.3...1.3.4.2...3.4.2.2...3.4.4.4
%e ...3.4.4.4...3.4.4.4...3.3.4.4...3.3.3.4...3.3.4.4...3.4.4.4...3.3.3.4
%K nonn
%O 2,2
%A _R. H. Hardin_ Aug 24 2009
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