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Number of n X n binary arrays symmetric under horizontal reflection with all ones connected only in two by two blocks.
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%I #3 Mar 31 2012 12:35:08

%S 1,2,1,4,6,31,37,642,380,14860,14318,905572,838039,131446789,91374201,

%T 32141426467,24653341080,17110758261851,12843811121650,

%U 19746616596912795,13295496951548212,44660433163764744504

%N Number of n X n binary arrays symmetric under horizontal reflection with all ones connected only in two by two blocks.

%e Maximal 7 X 7 example

%e .1.1.0.0.0.1.1

%e .1.1.0.0.0.1.1

%e .0.0.0.0.0.0.0

%e .0.0.0.0.0.0.0

%e .0.0.0.0.0.0.0

%e .0.1.1.0.1.1.0

%e .0.1.1.0.1.1.0

%K nonn

%O 1,2

%A _R. H. Hardin_, Oct 22 2008