%I #5 Mar 31 2012 12:37:30

%S 6466176,13183187396,26744766723116,54342179402121844,

%T 110373178905015566530,224204660538155238268018,

%U 455417252425855582254656088,925080790192116284005812399746

%N Half the number of (n+1)X8 0..2 arrays with every 2X2 subblock having at most one duplicate clockwise edge difference

%C Column 7 of A209951

%H R. H. Hardin, <a href="/A209950/b209950.txt">Table of n, a(n) for n = 1..210</a>

%e Some solutions for n=4

%e ..2..0..1..2..0..2..1..0....2..2..1..2..2..2..1..0....2..2..2..2..1..0..2..0

%e ..2..1..1..1..2..2..1..2....0..1..1..1..0..1..1..0....1..2..0..1..1..2..2..1

%e ..0..2..2..2..0..0..2..2....2..2..0..0..0..1..0..2....0..2..1..1..2..0..2..2

%e ..2..1..1..2..0..2..2..0....1..1..1..2..0..2..2..1....1..0..2..1..1..0..2..1

%e ..2..2..0..2..2..1..2..1....1..2..0..2..1..1..1..1....0..2..1..1..0..0..2..1

%K nonn

%O 1,1

%A _R. H. Hardin_ Mar 16 2012