A146425 - OEIS

A146425

Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1010-1111 pattern in any orientation.

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

%S 1,1,1,1,1,1,3,7,15,27,47,145,629,2639,10689,40727,200517,1226295,

%T 9011761,67694903,542738577,4721537297,50165476303,597630948157

%N Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1010-1111 pattern in any orientation.

%e Maximal 8 X 8 example

%e .0.0.0.1.0.1.0.0

%e .0.0.1.1.1.1.0.0

%e .0.1.0.0.0.0.1.1

%e .1.1.0.0.0.0.1.0

%e .0.1.0.0.0.0.1.1

%e .1.1.0.0.0.0.1.0

%e .0.0.1.1.1.1.0.0

%e .0.0.1.0.1.0.0.0

%K nonn

%O 1,7

%A _R. H. Hardin_