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%I #9 Apr 11 2022 13:15:49
%S 2,16,102,1970,57184,3511534,388134978,82999241712,33304563708790,
%T 25409866877400042,36648009080479725120,100161609586888545878490,
%U 518205987191621802807914102,5077481011895003740693688753360
%N Number of n X n 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 1 0 and 1 0 1 vertically.
%C Diagonal of A207808.
%H R. H. Hardin, <a href="/A207803/b207803.txt">Table of n, a(n) for n = 1..20</a>
%e Some solutions for n=4
%e ..1..0..1..1....1..1..0..0....0..1..0..0....0..1..1..0....1..0..1..1
%e ..0..1..0..0....1..1..1..0....0..1..1..0....0..1..1..0....0..1..1..0
%e ..0..1..0..0....0..1..1..1....0..1..1..0....1..0..1..0....0..1..0..0
%e ..1..0..1..0....0..1..1..1....0..1..1..1....1..0..1..1....0..1..0..0
%Y Cf. A207808.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 20 2012
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