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Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 10001-11111 pattern in any orientation.
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%I #4 Mar 31 2012 12:35:15

%S 1,1,1,1,1,1,1,1,3,5,9,15,27,43,124,355,1029,2971,10017,31249,124044,

%T 490643,2352059,10915093,60936189,323565841,2097402227

%N Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 10001-11111 pattern in any orientation.

%e Maximal 9 X 9 example

%e .0.0.1.0.0.0.1.0.0

%e .0.0.1.1.1.1.1.0.0

%e .1.1.0.0.0.0.0.1.1

%e .0.1.0.0.0.0.0.1.0

%e .0.1.0.0.0.0.0.1.0

%e .0.1.0.0.0.0.0.1.0

%e .1.1.0.0.0.0.0.1.1

%e .0.0.1.1.1.1.1.0.0

%e .0.0.1.0.0.0.1.0.0

%K nonn

%O 1,9

%A _R. H. Hardin_, Nov 04 2008