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%I #5 Nov 25 2018 17:31:30
%S 1,1,1,1,9,17,39,147,697,3223,21385,138955,1236361,11421757,147405903,
%T 1921739323,34678828327,635167573009,16140984723163,417732159981711,
%U 14999420093273161,546619996126234299,27635699247921456049
%N Number of n X n binary arrays symmetric under 90-degree rotation with all ones connected only in a 2 X 2 elbow 1,1 1,2 2,1 in any orientation.
%e Maximal 8 X 8 example:
%e 1 1 0 1 1 0 1 1
%e 1 0 1 0 1 0 0 1
%e 0 0 1 1 0 1 1 0
%e 1 1 0 0 0 1 0 1
%e 1 0 1 0 0 0 1 1
%e 0 1 1 0 1 1 0 0
%e 1 0 0 1 0 1 0 1
%e 1 1 0 1 1 0 1 1
%K nonn
%O 1,5
%A _R. H. Hardin_, Oct 25 2008
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