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%I #4 Dec 10 2012 18:14:27
%S 1,4,16,48,174,658,2482,9229,33982,125217,461351,1699127,6252129,
%T 22995280,84546207,310785413,1142206689,4197260747,15421867303,
%U 56659522539,208152496049,764662949438,2808941077111,10318186228202
%N Equals two maps: number of 2Xn binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal and antidiagonal neighbors in a random 0..1 2Xn array
%C Row 2 of A220328
%H R. H. Hardin, <a href="/A220329/b220329.txt">Table of n, a(n) for n = 1..210</a>
%e Some solutions for n=3
%e ..0..1..0....0..0..1....0..0..0....0..0..1....0..1..1....0..1..1....0..1..0
%e ..0..0..0....1..0..0....0..1..0....0..0..0....0..1..0....1..1..0....1..1..0
%K nonn
%O 1,2
%A _R. H. Hardin_ Dec 10 2012