%I A146680
%S A146680 1,1,1,1,1,1,1,9,20,33,56,137,404,1209,4087,15733,60343,254309,1153606,
%T A146680 5642466,31006709,182836767,1183007758,8378875432,64857203324
%N A146680 Number of n X n binary arrays symmetric under 90 degree rotation with 
               all ones connected only in a 1100-0111-1100 pattern in any orientation.
%e A146680 Maximal 8 X 8 example
%e A146680 .0.0.0.0.1.0.1.0
%e A146680 .1.1.0.0.1.1.1.0
%e A146680 .0.1.1.1.0.1.0.0
%e A146680 .1.1.0.0.0.1.0.0
%e A146680 .0.0.1.0.0.0.1.1
%e A146680 .0.0.1.0.1.1.1.0
%e A146680 .0.1.1.1.0.0.1.1
%e A146680 .0.1.0.1.0.0.0.0
%Y A146680 Sequence in context: A059108 A028566 A147479 this_sequence A143704 A128153 
               A109805
%Y A146680 Adjacent sequences: A146677 A146678 A146679 this_sequence A146681 A146682 
               A146683
%K A146680 nonn
%O A146680 1,8
%A A146680 Ron Hardin (rhhardin(AT)att.net), Nov 04 2008