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%I #7 Mar 31 2012 12:36:19
%S 44,363,6072,191360,10093200,935338785,154543989072,44556415740672,
%T 22668584136931568,20377347136466565883,32182451728510291871740,
%U 89502269428191719999392640,438593646987789744491801743584
%N Number of (n+2)X(n+2) symmetric binary matrices without the pattern 1 1 1 diagonally or antidiagonally
%H R. H. Hardin, <a href="/A190420/b190420.txt">Table of n, a(n) for n = 1..17</a>
%e Some solutions for n=2
%e ..1..1..0..1....1..1..0..0....1..1..1..0....0..1..0..0....1..0..0..1
%e ..1..1..0..0....1..1..0..0....1..0..1..0....1..0..0..0....0..0..0..1
%e ..0..0..0..0....0..0..0..0....1..1..0..0....0..0..1..1....0..0..0..0
%e ..1..0..0..0....0..0..0..1....0..0..0..1....0..0..1..0....1..1..0..0
%K nonn
%O 1,1
%A _R. H. Hardin_ May 10 2011
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