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A207891 Number of n X n 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 0 0 and 1 1 1 vertically.

%I A207891 #9 Jul 22 2025 20:56:32
%S A207891 2,16,84,870,11196,205258,5888458,243318702,13997746826,1221755612002,
%T A207891 156218303323950,28414320426633740,7652673923813342076,
%U A207891 3016400502880224884497,1720903600232362236817474
%N A207891 Number of n X n 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 0 0 and 1 1 1 vertically.
%C A207891 Diagonal of A207895
%H A207891 R. H. Hardin, <a href="/A207891/b207891.txt">Table of n, a(n) for n = 1..16</a>
%e A207891 Some solutions for n=4
%e A207891 ..0..0..1..1....1..1..0..0....1..1..0..0....1..1..1..1....0..0..1..0
%e A207891 ..1..1..1..1....0..0..1..0....0..0..1..1....1..1..0..0....1..1..0..0
%e A207891 ..0..1..0..0....0..1..1..1....1..1..0..0....0..0..1..0....0..1..1..1
%e A207891 ..0..0..1..0....1..0..0..1....1..0..0..1....1..0..0..1....1..0..0..1
%K A207891 nonn
%O A207891 1,1
%A A207891 _R. H. Hardin_ Feb 21 2012