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%I #9 Jan 25 2022 21:35:13
%S 2,16,102,987,13876,197256,3510185,71594896,1760487825,47844199134,
%T 1511863246821,57304254157049,2367852660685470,115523120639939042,
%U 6698200226978686505,429360115542695358515,32711874875890241470483
%N Number of n X n 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 0 1 0 vertically.
%C Diagonal of A207242.
%H R. H. Hardin, <a href="/A207236/b207236.txt">Table of n, a(n) for n = 1..21</a>
%e Some solutions for n=4
%e ..1..1..0..0....1..1..0..1....0..0..1..0....0..0..1..0....1..1..1..0
%e ..0..0..1..0....0..0..1..0....1..1..0..1....1..1..0..0....1..0..1..0
%e ..1..1..1..0....0..0..1..0....1..1..0..1....1..1..1..0....0..1..0..0
%e ..1..1..0..0....0..0..1..0....1..1..0..1....1..0..1..0....0..1..0..0
%Y Cf. A207242.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 16 2012