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A146031 Number of n X n binary arrays symmetric under horizontal reflection with all ones connected only in a 3X3 el 1,1 1,2 1,3 2,3 3,3 in any orientation. 0

%I

%S 1,1,1,1,1,1,47,87,827,1813,23847,61833,1905275,6035973,614447855,

%T 2474833329,318082536355,1576923345267,332168016129555,

%U 2011400450726835,916006897110162895,6848186045213206995,6424521065702879448173

%N Number of n X n binary arrays symmetric under horizontal reflection with all ones connected only in a 3X3 el 1,1 1,2 1,3 2,3 3,3 in any orientation.

%e Maximal 8 X 8 example

%e .1.1.1.0.0.1.1.1

%e .1.0.0.0.0.0.0.1

%e .1.0.0.0.0.0.0.1

%e .0.0.0.0.0.0.0.0

%e .0.0.0.0.0.0.0.0

%e .1.0.0.0.0.0.0.1

%e .1.0.0.0.0.0.0.1

%e .1.1.1.0.0.1.1.1

%K nonn

%O 1,7

%A _R. H. Hardin_, Oct 26 2008

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Last modified December 6 00:38 EST 2016. Contains 278771 sequences.