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Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a tee 1,1 1,2 1,3 2,2 in any orientation.
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%I #3 Mar 31 2012 12:35:08

%S 1,1,1,3,10,33,134,947,8780,97821,1375312,27712816,754977953,

%T 26645291289,1208294585650,74271003442168,6124346294290730,

%U 668846422203976047,95426817845827533968,18141398847837127162392

%N Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a tee 1,1 1,2 1,3 2,2 in any orientation.

%e Maximal 8 X 8 example

%e .0.0.0.1.0.0.0.1

%e .0.0.1.1.0.0.1.1

%e .0.1.0.1.0.0.0.1

%e .1.1.1.0.1.1.1.0

%e .0.0.0.1.0.1.0.1

%e .0.0.0.1.1.0.1.1

%e .0.1.0.1.0.1.0.1

%e .1.1.1.0.1.1.1.0

%K nonn

%O 1,4

%A _R. H. Hardin_, Oct 25 2008