%I #5 Mar 31 2012 12:37:30
%S 62,13098,16664508,135833193008,6954596004028468,
%T 2253166071062026531552,4605826850905941430535864352,
%U 59470527831535893681344131012059952
%N Half the number of (n+1)X(n+1) 0..3 arrays with every 2X2 subblock having two or four distinct clockwise edge differences
%C Diagonal of A209913
%e Some solutions for n=4
%e ..0..2..2..1..0....3..0..3..3..0....1..0..0..0..0....3..0..0..1..1
%e ..3..3..0..2..3....0..3..0..1..3....3..1..3..1..3....1..3..1..3..0
%e ..0..1..3..3..2....1..0..1..0..1....1..3..1..3..0....0..0..3..1..1
%e ..3..1..0..1..3....1..3..3..2..3....1..0..3..0..1....3..1..0..0..3
%e ..3..0..1..3..1....2..1..0..0..3....0..1..1..0..3....0..3..3..2..2
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 15 2012
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