A146718 - OEIS

A146718

Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1100-1111-1000 pattern in any orientation.

%I #4 Mar 31 2012 12:35:12

%S 1,1,1,1,1,1,1,1,7,13,27,41,107,327,1681,5451,24597,80545,454313,

%T 2226033,18080203,106915629

%N Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1100-1111-1000 pattern in any orientation.

%e Maximal 9 X 9 example

%e .0.0.0.0.0.1.0.0.0

%e .0.0.1.1.1.1.0.0.0

%e .0.1.0.0.1.1.0.0.0

%e .0.1.0.0.0.0.1.1.1

%e .0.1.1.0.0.0.1.1.0

%e .1.1.1.0.0.0.0.1.0

%e .0.0.0.1.1.0.0.1.0

%e .0.0.0.1.1.1.1.0.0

%e .0.0.0.1.0.0.0.0.0

%K nonn

%O 1,9

%A _R. H. Hardin_, Nov 04 2008