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%I #3 Dec 26 2012 21:13:26
%S 1,23,142,1769,15640,135445,1135785,9319689,75739525,610550298,
%T 4906067283,39329548159,314985289528,2521161457137
%N Equals two maps: number of 3Xn binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal, diagonal and antidiagonal neighbors in a random 0..3 3Xn array
%C Row 3 of A220959
%e Some solutions for n=3
%e ..0..0..0....0..0..1....1..1..1....0..0..0....0..1..0....0..1..0....0..0..0
%e ..0..0..1....0..0..0....0..0..0....0..1..1....0..1..0....0..1..1....1..1..1
%e ..1..0..1....0..1..0....0..0..0....0..1..1....1..1..1....1..1..0....0..0..0
%K nonn
%O 1,2
%A _R. H. Hardin_ Dec 26 2012