A147487 - OEIS

A147487

Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 11011-01110-00100 pattern in any orientation.

%I #4 Mar 31 2012 12:35:17

%S 1,1,1,1,1,1,4,7,13,21,47,71,266,697,2575,7222,30644,93493,472633,

%T 1837587,10941522,49363521,346195883,1801870833

%N Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 11011-01110-00100 pattern in any orientation.

%e Maximal 8 X 8 example

%e .1.0.0.1.1.0.1.1

%e .1.1.0.0.1.1.1.0

%e .0.1.1.0.0.1.0.0

%e .1.1.0.0.0.0.0.1

%e .1.0.0.0.0.0.1.1

%e .0.0.1.0.0.1.1.0

%e .0.1.1.1.0.0.1.1

%e .1.1.0.1.1.0.0.1

%K nonn

%O 1,7

%A _R. H. Hardin_