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%I #4 Dec 18 2015 18:17:26
%S 2,16,400,28561,7133488,5037592576,11494250657760,81903288018125025,
%T 1774095560440527819780,120560883729040740095954944,
%U 25387802734116842287569948104640,16523941893729018365186706701633818689
%N Number of n X n binary matrices with no three 1's adjacent in a line diagonally or antidiagonally
%C Diagonal of A181217
%H R. H. Hardin, <a href="/A181213/b181213.txt">Table of n, a(n) for n=1..20</a>
%e Some avoided solutions for 4X4
%e ..1..0..0..0....0..0..0..0....0..0..0..1....0..1..0..0....0..0..1..0
%e ..0..1..0..0....0..0..1..1....0..1..1..0....0..0..1..0....0..1..0..0
%e ..0..0..1..1....0..0..1..0....0..1..0..0....1..0..0..1....1..0..0..0
%e ..0..0..0..0....0..1..0..0....0..0..0..0....0..0..0..0....0..0..1..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Oct 10 2010