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Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1000-1111-0001 pattern in any orientation.
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%I #4 Mar 31 2012 12:35:11

%S 1,1,1,1,1,1,1,1,9,9,29,29,137,137,1079,1079,13093,13093,250867,

%T 250867,6233403,6233403,218750525,218750525,11495073517,11495073517,

%U 872282781415

%N Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1000-1111-0001 pattern in any orientation.

%e Maximal 9 X 9 example

%e .0.0.0.0.0.0.0.0.0

%e .1.0.0.0.0.0.0.0.1

%e .1.1.1.1.0.1.1.1.1

%e .0.0.0.1.0.1.0.0.0

%e .0.0.0.0.0.0.0.0.0

%e .0.0.0.1.0.1.0.0.0

%e .1.1.1.1.0.1.1.1.1

%e .1.0.0.0.0.0.0.0.1

%e .0.0.0.0.0.0.0.0.0

%K nonn

%O 1,9

%A _R. H. Hardin_, Nov 04 2008