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A145810 Number of islands of ones fitting in an n X n array symmetric under horizontal reflection with all ones connected only either three adjacent vertically or three adjacent horizontally. 0

%I

%S 0,0,2,2,4,4,8,8,14,12,20,20,27,28,38,36,47,48

%N Number of islands of ones fitting in an n X n array symmetric under horizontal reflection with all ones connected only either three adjacent vertically or three adjacent horizontally.

%e 8 X 8 example with 8 islands

%e .1.1.1.0.0.1.1.1

%e .0.0.0.0.0.0.0.0

%e .0.0.0.0.0.0.0.0

%e .1.1.1.0.0.1.1.1

%e .0.0.0.0.0.0.0.0

%e .1.0.1.0.0.1.0.1

%e .1.0.1.0.0.1.0.1

%e .1.0.1.0.0.1.0.1

%K nonn

%O 1,3

%A _R. H. Hardin_, Oct 20 2008

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Last modified November 18 01:20 EST 2018. Contains 317279 sequences. (Running on oeis4.)