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%I #5 Nov 25 2018 13:04:00
%S 1,2,1,5,17,65,213,1787,9524,116339,1060737,20603151,287231280,
%T 9041569891,204033795980,10154300111410,365136416788873,
%U 29097460058976118,1667205355351243670
%N Number of n X n binary arrays, symmetric under 90-degree rotation, with every 1 adjacent to at least one other 1, but at most one 1 adjacent horizontally and at most one 1 adjacent vertically.
%K nonn
%O 1,2
%A _R. H. Hardin_, Sep 08 2008