%I A145957
%S A145957 1,1,1,1,1,1,1,1,3,3,9,9,23,23,125,125,821,821,6239,6239,71403,71403,
%T A145957 1048093,1048093,19913069,19913069,517074745,517074745,17642361171,
%U A145957 17642361171
%N A145957 Number of n X n binary arrays symmetric about the diagonal and under
90 degree rotation with all ones connected only in a zee 1,1 1,2
2,2 2,3 in any orientation.
%e A145957 Maximal 9 X 9 example
%e A145957 .0.0.1.0.0.0.1.0.0
%e A145957 .0.0.1.1.0.1.1.0.0
%e A145957 .1.1.0.1.0.1.0.1.1
%e A145957 .0.1.1.0.0.0.1.1.0
%e A145957 .0.0.0.0.0.0.0.0.0
%e A145957 .0.1.1.0.0.0.1.1.0
%e A145957 .1.1.0.1.0.1.0.1.1
%e A145957 .0.0.1.1.0.1.1.0.0
%e A145957 .0.0.1.0.0.0.1.0.0
%Y A145957 Sequence in context: A146394 A147510 A146474 this_sequence A128019 A108411
A056449
%Y A145957 Adjacent sequences: A145954 A145955 A145956 this_sequence A145958 A145959
A145960
%K A145957 nonn
%O A145957 1,9
%A A145957 Ron Hardin (rhhardin(AT)att.net), Oct 25 2008
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