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A164753 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 0

%I

%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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Last modified October 5 05:10 EDT 2022. Contains 357252 sequences. (Running on oeis4.)