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%I #4 Mar 31 2012 12:36:34
%S 51,90641,203087097,468268681671,1088857594220452
%N Number of 2nX12 0..4 arrays with values 0..4 introduced in row major order and each element equal to exactly two horizontal and vertical neighbors
%C Column 6 of A198253
%e Some solutions for n=3
%e ..0..0..0..0..0..0..0..0..0..0..1..1....0..0..0..0..0..0..1..1..0..0..1..1
%e ..0..2..2..3..3..4..4..1..1..0..1..1....0..2..2..3..3..0..1..1..0..0..1..1
%e ..0..2..2..3..3..4..4..1..1..0..0..0....0..2..2..3..3..0..3..3..1..1..2..2
%e ..0..4..4..0..0..0..0..0..0..4..4..0....0..0..0..0..0..0..3..3..1..1..2..2
%e ..0..4..4..0..1..1..4..4..0..4..4..0....2..2..4..4..3..3..1..1..2..2..0..0
%e ..0..0..0..0..1..1..4..4..0..0..0..0....2..2..4..4..3..3..1..1..2..2..0..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Oct 22 2011
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