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%I #5 Nov 25 2018 12:29:22
%S 1,1,1,2,2,3,6,10,21,46,106,253,820,2128,8527,25843,122734,425169,
%T 2572337,9924088,75407076,331598798,3087553649,15467749658,
%U 179756366268,1016119110332,14755861942091,94597276047265,1702584089571489
%N Number of n X n binary arrays symmetric about the diagonal and under 90-degree rotation with all ones connected only either two adjacent vertically or two adjacent horizontally.
%K nonn
%O 1,4
%A _R. H. Hardin_, Oct 18 2008
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