%I #5 Nov 25 2018 13:03:08
%S 1,1,1,4,8,17,58,224,939,4970,30996,225413,1970184,20575972,252185309,
%T 3690646219,64088665934,1323737025941,32350145726565,942783467265088,
%U 32507076170340916,1335377761740727698,64933573760903971267
%N Number of n X n binary arrays symmetric 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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