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%I
%S 1,3,7,72,866,16660,401634,11891268,413867410,16583242015
%N Number of n-bead necklaces labeled with numbers -n..n allowing reversal, with sum zero and avoiding the patterns z z+1 z+2 and z z-1 z-2.
%C Diagonal of A209485.
%e Some solutions for n=6:
%e .-6...-3...-6...-6...-6...-6...-6...-4...-6...-6...-6...-6...-2...-6...-6...-5
%e ..2...-2...-1....0....4....2...-4...-4....2....0...-4....0...-1...-4...-1...-3
%e ..6....0...-2....0....0....2....5...-2...-2....1....1...-2....1....1....3....0
%e .-5....0....4...-2...-3....2....0....2....1....0....5...-2...-1....1....3....3
%e .-2....6....2....3...-1...-4....2....4....0....5....3....5....1....5...-2....6
%e ..5...-1....3....5....6....4....3....4....5....0....1....5....2....3....3...-1
%K nonn
%O 1,2
%A _R. H. Hardin_, Mar 09 2012
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