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Number of n X n binary arrays symmetric under horizontal and vertical reflection 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 1,1,1,1,6,1,38,9,408,33,7604,404,271731,7941,15992426,262632,

%T 1666574068,14831415,309972197784,1538127410,100682581657471,

%U 275592188347,57498326956771300,87279885007004,57832081083719379686

%N Number of n X n binary arrays symmetric under horizontal and vertical reflection 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 .0.0.0.0.0.0.0.0

%e .0.1.0.0.0.0.1.0

%e .1.1.1.0.0.1.1.1

%e .0.0.0.0.0.0.0.0

%e .0.0.0.0.0.0.0.0

%e .1.1.1.0.0.1.1.1

%e .0.1.0.0.0.0.1.0

%e .0.0.0.0.0.0.0.0

%K nonn

%O 1,5

%A _R. H. Hardin_, Oct 25 2008