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%I #5 Sep 03 2022 20:56:15
%S 1,37,508,6657,92093,1335202,18836493,265346645,3750121527
%N Equals two maps: number of 4 X n binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal and antidiagonal neighbors in a random 0..1 4 X n array.
%C Row 4 of A220328.
%e Some solutions for n=3
%e ..0..0..1....0..1..0....0..0..0....0..0..1....0..0..1....0..1..0....0..0..1
%e ..1..0..1....0..1..0....0..1..1....1..0..0....1..1..0....0..1..0....0..0..0
%e ..0..0..1....1..0..0....0..0..0....0..1..0....0..0..1....1..1..1....0..0..0
%e ..1..0..0....0..0..0....0..1..0....0..1..0....0..0..0....0..1..0....1..1..0
%Y Cf. A220328.
%K nonn
%O 1,2
%A _R. H. Hardin_, Dec 10 2012