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A207461 Number of n X n 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 1 0 and 1 0 1 vertically.

%I A207461 #9 Jul 22 2025 20:27:23
%S A207461 2,16,98,1307,21517,491948,16675001,760840082,48694010408,
%T A207461 4485988205726,562936265068141,102307352557957161,
%U A207461 26014225086453944774,9391676528481972080755,4844995109176631213739332
%N A207461 Number of n X n 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 1 0 and 1 0 1 vertically.
%C A207461 Diagonal of A207467
%H A207461 R. H. Hardin, <a href="/A207461/b207461.txt">Table of n, a(n) for n = 1..18</a>
%e A207461 Some solutions for n=4
%e A207461 ..0..0..1..0....0..0..1..0....1..1..0..1....1..1..0..0....0..1..0..1
%e A207461 ..1..1..1..1....1..1..0..1....0..0..1..0....1..0..0..1....0..0..1..0
%e A207461 ..1..1..1..1....1..1..0..1....0..0..1..0....1..0..0..1....1..0..1..0
%e A207461 ..0..1..0..0....0..1..0..1....1..0..1..0....0..0..1..0....1..0..1..0
%K A207461 nonn
%O A207461 1,1
%A A207461 _R. H. Hardin_ Feb 18 2012