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%I #7 Dec 18 2015 18:17:37
%S 2,16,400,23716,3179520,953574400,627097603968,924914073760000,
%T 3050440754161147200,22736725050654514945600,
%U 381669581712710598918922368,14487934510226746411430441441536,1241349850723840266193329456972217472
%N Number of n X n binary arrays without the pattern 1 1 0 diagonally or antidiagonally
%C Diagonal of A189111
%H R. H. Hardin, <a href="/A189104/b189104.txt">Table of n, a(n) for n = 1..19</a>
%e Some solutions for 3X3
%e ..0..1..0....1..0..1....0..1..0....0..1..1....0..0..0....0..0..1....1..1..0
%e ..1..0..1....0..1..0....0..1..1....0..1..1....1..0..1....1..0..0....0..0..1
%e ..1..0..0....1..0..1....0..0..0....1..1..0....0..1..1....0..0..1....0..0..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Apr 16 2011