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%I #3 Jan 09 2013 12:48:57
%S 1,37,556,9107,172904,2890017,49684593,821323042,13475380990
%N Equals two maps: number of 4Xn binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal and antidiagonal neighbors in a random 0..3 4Xn array
%C Row 4 of A221290
%e Some solutions for n=3
%e ..0..1..0....0..0..0....0..0..1....0..1..0....0..1..1....0..1..0....0..0..1
%e ..0..0..0....0..1..0....0..1..0....0..1..0....1..1..0....1..0..0....1..0..0
%e ..1..1..0....0..1..1....1..1..1....1..0..0....0..0..0....0..0..1....0..1..1
%e ..0..0..0....1..1..0....0..0..0....0..1..0....1..1..0....0..0..0....1..0..0
%K nonn
%O 1,2
%A _R. H. Hardin_ Jan 09 2013