A146260 - OEIS

A146260

Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 110-111-101 pattern in any orientation.

%I #4 Mar 31 2012 12:35:09

%S 1,1,1,1,1,1,1,5,13,25,47,113,351,1317,5315,24057,110167,558903,

%T 3123765,20513901,147650027,1233473669,10827756731

%N Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 110-111-101 pattern in any orientation.

%e Maximal 8 X 8 example

%e .0.0.0.1.0.1.0.0

%e .0.0.0.1.1.1.0.0

%e .0.0.0.1.1.0.1.1

%e .1.1.1.0.0.1.1.0

%e .0.1.1.0.0.1.1.1

%e .1.1.0.1.1.0.0.0

%e .0.0.1.1.1.0.0.0

%e .0.0.1.0.1.0.0.0

%K nonn

%O 1,8

%A _R. H. Hardin_