%I A146053
%S A146053 1,1,1,5,29,139,901,5485,74291,1056181,24810777,651071773,25748617719,
%T A146053 1169149922235,81072042123257,6590052771959131
%N A146053 Number of n X n binary arrays symmetric under 180 degree rotation with 
               all ones connected only in a 2X2 block with tail 1,1 1,2 1,3 2,2 
               2,3 in any orientation.
%e A146053 Maximal 8 X 8 example
%e A146053 .1.1.0.1.0.1.1.1
%e A146053 .1.1.0.1.1.0.1.1
%e A146053 .1.0.0.1.1.0.0.0
%e A146053 .0.1.1.0.0.1.1.1
%e A146053 .1.1.1.0.0.1.1.0
%e A146053 .0.0.0.1.1.0.0.1
%e A146053 .1.1.0.1.1.0.1.1
%e A146053 .1.1.1.0.1.0.1.1
%Y A146053 Sequence in context: A153077 A000352 A034332 this_sequence A163082 A060963 
               A107002
%Y A146053 Adjacent sequences: A146050 A146051 A146052 this_sequence A146054 A146055 
               A146056
%K A146053 nonn
%O A146053 1,4
%A A146053 Ron Hardin (rhhardin(AT)att.net), Oct 26 2008