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%I #6 Mar 12 2017 23:23:04
%S 1,4,12,57,274,1464,7974,45050,260046,1529746,9129838,55159410,
%T 336661016,2072786142,12858170994,80288297320,504231724034
%N Number of n-bead necklaces labeled with numbers -3..3 not allowing reversal, with sum zero with no three beads in a row equal.
%C Column 3 of A208945.
%e Some solutions for n=5:
%e .-2...-3...-3...-3...-3...-2...-3...-2...-2...-3...-3...-2...-3...-3...-2...-2
%e ..1...-2....2....0....3....2....1....1...-2...-3....3...-2...-1...-1....0...-1
%e .-1....3....1....0...-2...-2....1....1....0....3...-3....2....3....3...-1....2
%e .-1....3...-1....3....2....3....2...-2....2....0....3....3....3...-2....2...-2
%e ..3...-1....1....0....0...-1...-1....2....2....3....0...-1...-2....3....1....3
%K nonn
%O 1,2
%A _R. H. Hardin_, Mar 03 2012
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