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%I #6 Mar 12 2017 23:37:08
%S 1,6,17,128,883,7358,62853,563109,5153746,48127107,456011561,
%T 4374662802,42398844001
%N Number of n-bead necklaces labeled with numbers -5..5 allowing reversal, with sum zero with no three beads in a row equal.
%C Column 5 of A209344.
%e Some solutions for n=7:
%e .-4...-5...-5...-5...-3...-3...-5...-4...-3...-5...-3...-4...-4...-5...-4...-3
%e .-3....1...-4....2...-2....0....0...-1....1....3...-1...-1...-2...-2...-2...-2
%e ..1....3....0....2....0....3...-3....2....2....0....5....5....1....1....5....0
%e ..4....1....5...-3....2...-1....5....0...-2...-2...-2...-3....2....0...-4....5
%e .-3...-2....4...-2....0...-1....4....2...-2...-2....1...-3....0....5....0...-3
%e ..4...-1...-1....2....0...-2...-5...-1....0....2...-2....1...-1...-3....1....3
%e ..1....3....1....4....3....4....4....2....4....4....2....5....4....4....4....0
%K nonn
%O 1,2
%A _R. H. Hardin_, Mar 06 2012