A146861 - OEIS

A146861

Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1101-0111-0100 pattern in any orientation.

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

%S 1,1,1,1,1,1,5,19,37,77,131,515,1575,6459,26455,139873,647697,4036849,

%T 21133021,162531941,1088442077

%N Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1101-0111-0100 pattern in any orientation.

%e Maximal 8 X 8 example

%e .0.0.1.0.1.1.0.0

%e .0.0.1.1.1.0.0.0

%e .1.0.0.0.1.0.1.1

%e .1.1.1.0.0.0.1.0

%e .0.1.0.0.0.1.1.1

%e .1.1.0.1.0.0.0.1

%e .0.0.0.1.1.1.0.0

%e .0.0.1.1.0.1.0.0

%K nonn

%O 1,7

%A _R. H. Hardin_, Nov 04 2008