%I #7 Oct 19 2021 21:39:19

%S 31926146,78298719958,174099838817590,395928291655518846,

%T 896278100477366851795,2032217168415654090395276,

%U 4605826850905941430535864352,10440431207754050038448850990818

%N Half the number of (n+1) X 8 0..3 arrays with every 2 X 2 subblock having two or four distinct clockwise edge differences.

%C Column 7 of A209913.

%H R. H. Hardin, <a href="/A209912/b209912.txt">Table of n, a(n) for n = 1..210</a>

%e Some solutions for n=4

%e ..3..3..2..0..0..2..1..1....0..2..3..2..3..3..2..3....3..2..0..3..3..3..2..3

%e ..0..1..0..1..3..3..0..3....0..3..1..3..0..2..3..0....0..0..3..0..1..0..1..0

%e ..0..3..3..0..1..0..1..3....2..2..0..1..3..2..0..2....2..3..0..1..0..1..0..3

%e ..2..0..1..3..0..1..0..0....3..0..1..0..2..1..2..3....3..0..3..1..3..1..3..0

%e ..0..1..3..0..1..2..3..1....3..1..3..3..3..0..1..0....3..1..1..2..1..0..1..1

%Y Cf. A209913.

%K nonn

%O 1,1

%A _R. H. Hardin_ Mar 15 2012