A146436 - OEIS

A146436

Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 101-111-101 pattern in any orientation.

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

%S 1,1,3,1,3,9,23,73,239,601,4153,14191,114759,580339,5550888,46368603,

%T 562683992,5393792447,97221007962,1178726702163,29671069397702,

%U 489244079163479

%N Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 101-111-101 pattern in any orientation.

%e Maximal 8 X 8 example

%e .1.1.1.0.0.0.0.0

%e .0.1.0.0.1.0.1.0

%e .1.1.1.0.1.1.1.0

%e .0.0.0.0.1.0.1.0

%e .0.1.0.1.0.0.0.0

%e .0.1.1.1.0.1.1.1

%e .0.1.0.1.0.0.1.0

%e .0.0.0.0.0.1.1.1

%K nonn

%O 1,3

%A _R. H. Hardin_