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%I #5 Mar 31 2012 12:36:19
%S 39,240,2271,35661,836514,27940563,1374170474,102369944843,
%T 11464683896495,1905358977494462,469934471799881606,
%U 172863979596481949179,94947989820190085424440
%N Number of (n+2)X(n+2) symmetric binary matrices without the pattern 1 0 1 diagonally, vertically or horizontally
%H R. H. Hardin, <a href="/A190606/b190606.txt">Table of n, a(n) for n = 1..14</a>
%e Some solutions for 4X4
%e ..0..0..1..1....0..0..1..1....0..0..0..1....0..0..1..0....0..0..1..0
%e ..0..0..1..1....0..1..1..1....0..0..1..0....0..0..1..0....0..0..1..1
%e ..1..1..0..0....1..1..1..1....0..1..0..0....1..1..1..0....1..1..1..1
%e ..1..1..0..0....1..1..1..0....1..0..0..1....0..0..0..1....0..1..1..0
%K nonn
%O 1,1
%A _R. H. Hardin_ May 13 2011