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Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 2X4 el 1,1 1,2 1,3 1,4 2,4 with any orientation.
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%I #3 Mar 31 2012 12:35:08

%S 1,1,1,1,1,1,3,7,15,29,61,211,895,3955,16593,80999,462679,3239573,

%T 25414255,222500583,2101470837,23313975471,290908388247,4246548210105,

%U 68354920234083

%N Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 2X4 el 1,1 1,2 1,3 1,4 2,4 with any orientation.

%e Maximal 8 X 8 example

%e .0.0.0.0.0.1.0.0

%e .0.0.1.1.1.1.0.0

%e .0.1.0.0.0.0.1.1

%e .0.1.0.0.0.0.1.0

%e .0.1.0.0.0.0.1.0

%e .1.1.0.0.0.0.1.0

%e .0.0.1.1.1.1.0.0

%e .0.0.1.0.0.0.0.0

%K nonn

%O 1,7

%A _R. H. Hardin_, Oct 26 2008