A146393 - OEIS

A146393

Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1000-1100-0111 pattern in any orientation.

%I #4 Mar 31 2012 12:35:10

%S 1,1,1,1,1,1,1,3,9,19,43,141,419,1255,5087,24913,131971,734375,

%T 4818949,34664741,269727721,2371934855,24159321229,274622983853

%N Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1000-1100-0111 pattern in any orientation.

%e Maximal 8 X 8 example

%e .0.1.1.1.0.0.0.0

%e .1.0.0.1.1.0.0.0

%e .1.0.0.0.1.0.0.0

%e .1.1.0.0.0.1.1.0

%e .0.1.1.0.0.0.1.1

%e .0.0.0.1.0.0.0.1

%e .0.0.0.1.1.0.0.1

%e .0.0.0.0.1.1.1.0

%K nonn

%O 1,8

%A _R. H. Hardin_