A146717 - OEIS

A146717

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

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

%S 1,1,1,1,1,5,17,39,155,745,4705,39573,369483,3970963,54943873,

%T 950039207,20417177215,545483266919,17663079620537,695250063366563,

%U 33778790635375371

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

%e Maximal 8 X 8 example

%e .0.0.0.1.1.1.0.0

%e .0.0.0.1.1.0.1.0

%e .0.0.0.0.1.0.1.0

%e .1.1.0.0.1.0.1.1

%e .1.1.1.1.0.1.1.1

%e .1.0.0.0.1.0.0.0

%e .0.1.1.1.1.0.0.0

%e .0.0.0.1.1.0.0.0

%K nonn

%O 1,6

%A _R. H. Hardin_, Nov 04 2008