A146645 - OEIS

A146645

Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1010-1111-1000 pattern in any orientation.

%I #4 Mar 31 2012 12:35:11

%S 1,1,1,1,1,5,17,39,143,759,4705,36573,332389,3601255,48371515,

%T 827745175,17238229681,441854255629,13777843130457,527986032874649,

%U 24769703202602783

%N Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1010-1111-1000 pattern in any orientation.

%e Maximal 8 X 8 example

%e .0.0.0.1.1.1.0.0

%e .0.0.0.0.1.0.1.0

%e .0.0.0.1.1.0.1.1

%e .1.0.1.0.1.0.1.0

%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 .0.0.1.0.1.0.0.0

%K nonn

%O 1,6

%A _R. H. Hardin_, Nov 04 2008