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A207263 Number of n X n 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 1 1 and 1 0 1 vertically.

%I A207263 #9 Jul 22 2025 20:13:07
%S A207263 2,16,82,611,5904,45520,467686,4556171,48655983,567847595,6351729691,
%T A207263 80023297510,1005050679531,12834603243934,174354454607454,
%U A207263 2353308940308585,32870079608035300,470039857440029540
%N A207263 Number of n X n 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 1 1 and 1 0 1 vertically.
%C A207263 Diagonal of A207269
%H A207263 R. H. Hardin, <a href="/A207263/b207263.txt">Table of n, a(n) for n = 1..23</a>
%e A207263 Some solutions for n=4
%e A207263 ..1..0..0..1....0..1..0..1....1..1..0..1....1..0..0..1....0..0..1..0
%e A207263 ..0..1..0..0....0..1..0..0....0..1..0..1....0..0..1..0....1..1..1..0
%e A207263 ..0..0..1..0....1..1..0..0....0..1..0..1....0..1..0..0....0..0..1..0
%e A207263 ..1..0..0..1....0..1..0..1....1..0..1..0....1..0..0..1....0..0..1..0
%K A207263 nonn
%O A207263 1,1
%A A207263 _R. H. Hardin_ Feb 16 2012