%I #6 Mar 12 2017 23:22:26
%S 1,3,6,22,68,264,988,3954,15980,66146,277190,1177152,5047672,21838420,
%T 95184446,417606390,1842715198,8172736366,36412668752,162897497434,
%U 731442664136
%N Number of n-bead necklaces labeled with numbers -2..2 not allowing reversal, with sum zero with no three beads in a row equal.
%C Column 2 of A208945.
%e Some solutions for n=5:
%e .-2...-2...-2...-2...-1...-2...-2...-2...-2...-2...-2...-2...-2...-1...-1...-1
%e .-1...-2....1....2....0....0....1....0...-1....2....0....1...-1...-1...-1....0
%e .-1....2....0....1....0....2....1....1....0....1....0....2....0....2....1...-1
%e ..2....1....0....0...-1...-2...-2...-1....1...-1....1...-1....2...-1....0....0
%e ..2....1....1...-1....2....2....2....2....2....0....1....0....1....1....1....2
%K nonn
%O 1,2
%A _R. H. Hardin_, Mar 03 2012
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