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Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 0111-1100-0111 pattern in any orientation.
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%I #4 Mar 31 2012 12:35:16

%S 1,1,1,1,1,1,1,1,4,7,14,21,40,79,252,611,2359,6199,23158,70484,325136,

%T 1222235,6869095,29506240,189032773,936666179

%N Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 0111-1100-0111 pattern in any orientation.

%e Maximal 9 X 9 example

%e .0.0.0.1.0.1.0.0.0

%e .0.0.0.1.0.1.0.0.0

%e .0.0.0.1.1.1.0.0.0

%e .1.1.1.0.1.0.1.1.1

%e .0.0.1.1.0.1.1.0.0

%e .1.1.1.0.1.0.1.1.1

%e .0.0.0.1.1.1.0.0.0

%e .0.0.0.1.0.1.0.0.0

%e .0.0.0.1.0.1.0.0.0

%K nonn

%O 1,9

%A _R. H. Hardin_