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A145999 Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 3X3 plus 2,1 2,2 2,3 1,2 3,2. 0

%I #3 Mar 31 2012 12:35:08

%S 1,1,2,1,2,1,7,2,23,5,132,12,836,51,8563,317,115954,2654,2274857,

%T 30351,60964251,489559,2304941344,11104536,120886008663,350752586,

%U 8909697213591,15493779226,915528841065256,954798521885

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

%e Maximal 8 X 8 example

%e .0.1.0.0.0.0.1.0

%e .1.1.1.0.0.1.1.1

%e .0.1.0.0.0.0.1.0

%e .0.0.0.0.0.0.0.0

%e .0.0.0.0.0.0.0.0

%e .0.1.0.0.0.0.1.0

%e .1.1.1.0.0.1.1.1

%e .0.1.0.0.0.0.1.0

%K nonn

%O 1,3

%A _R. H. Hardin_, Oct 26 2008

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Last modified April 16 13:50 EDT 2024. Contains 371724 sequences. (Running on oeis4.)