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A221292 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.

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%I A221292 #5 Jul 23 2025 01:49:25
%S A221292 1,37,556,9107,172904,2890017,49684593,821323042,13475380990
%N A221292 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 A221292 Row 4 of A221290
%e A221292 Some solutions for n=3
%e A221292 ..0..1..0....0..0..0....0..0..1....0..1..0....0..1..1....0..1..0....0..0..1
%e A221292 ..0..0..0....0..1..0....0..1..0....0..1..0....1..1..0....1..0..0....1..0..0
%e A221292 ..1..1..0....0..1..1....1..1..1....1..0..0....0..0..0....0..0..1....0..1..1
%e A221292 ..0..0..0....1..1..0....0..0..0....0..1..0....1..1..0....0..0..0....1..0..0
%K A221292 nonn
%O A221292 1,2
%A A221292 _R. H. Hardin_ Jan 09 2013

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