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%I #6 Mar 13 2017 00:00:27
%S 1,5,20,122,766,5239,37108,271732,2035161,15526728,120213839,
%T 942210714,7461093141,59602526850,479745735803
%N Number of n-bead necklaces labeled with numbers -4..4 not allowing reversal, with sum zero and avoiding the pattern z z+1 z+2.
%C Column 4 of A209073.
%e Some solutions for n=6:
%e .-3...-2...-3...-4...-3...-4...-1...-2...-3...-3...-4...-3...-4...-4...-2...-1
%e ..3...-2....3....3....4...-3...-1....0....2...-1...-2....4...-2...-1...-1...-1
%e .-1...-2....1...-1...-2....2...-1...-2....3....0....2...-1....3....2...-1....2
%e .-3....3...-2....4....3....1...-1....0...-2...-1....3....0....3....2....4....0
%e ..4....0....3....1...-2....0....4....1....2....2....3...-2...-4....4...-2....0
%e ..0....3...-2...-3....0....4....0....3...-2....3...-2....2....4...-3....2....0
%K nonn
%O 1,2
%A _R. H. Hardin_, Mar 04 2012
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