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A208374 Number of n X n 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 1 0 1 vertically.

%I A208374 #9 Jul 22 2025 21:18:40
%S A208374 2,16,72,420,2176,10660,60984,340816,1846240,11076228,66303360,
%T A208374 390426916,2456007216,15586002640,98058552648,645057461220,
%U A208374 4299810563584,28563593727716,195777751059000,1361449965542992,9468978890210480
%N A208374 Number of n X n 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 1 0 1 vertically.
%C A208374 Diagonal of A208379
%H A208374 R. H. Hardin, <a href="/A208374/b208374.txt">Table of n, a(n) for n = 1..39</a>
%e A208374 Some solutions for n=4
%e A208374 ..1..1..0..0....1..0..0..1....1..0..0..1....1..1..0..1....1..0..0..1
%e A208374 ..1..1..0..0....1..1..0..0....0..1..1..0....1..1..0..1....0..1..0..1
%e A208374 ..0..1..0..0....1..1..0..0....0..0..1..0....1..1..0..1....0..1..0..0
%e A208374 ..0..1..0..0....1..1..0..0....0..0..1..0....0..1..0..1....0..1..0..0
%K A208374 nonn
%O A208374 1,1
%A A208374 _R. H. Hardin_ Feb 25 2012