A146424 - OEIS

A146424

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

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

%S 1,1,1,1,3,13,35,165,727,4597,49361,536263,7236179,123419355,

%T 2560850455,72571417743,2591027414559,113550328451315,

%U 6265506511430339,433231100847867929

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

%e Maximal 8 X 8 example

%e .0.0.0.1.1.0.0.0

%e .0.0.0.0.1.0.0.0

%e .0.0.0.1.1.0.0.0

%e .1.0.1.0.1.0.1.1

%e .1.1.1.1.0.0.0.1

%e .0.0.0.0.0.0.1.1

%e .0.0.0.1.0.1.0.1

%e .0.0.0.1.1.1.1.0

%K nonn

%O 1,5

%A _R. H. Hardin_