A146818 - OEIS

A146818

Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1000-1110-0111 pattern in any orientation.

%I #4 Mar 31 2012 12:35:14

%S 1,1,1,1,3,9,23,59,317,2143,14651,111875,1267355,18704275,315484781,

%T 6350976523,167797579971,5630142919363,228828878480313

%N Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1000-1110-0111 pattern in any orientation.

%e Maximal 8 X 8 example

%e .0.0.1.1.0.0.0.0

%e .0.0.0.1.1.0.0.1

%e .1.0.0.1.1.0.1.1

%e .1.1.1.0.1.0.1.1

%e .0.1.1.1.0.1.1.0

%e .0.0.0.0.1.0.0.0

%e .0.0.1.1.1.0.0.0

%e .0.1.1.1.0.0.0.0

%K nonn

%O 1,5

%A _R. H. Hardin_, Nov 04 2008