%I #6 Mar 13 2017 00:08:55
%S 1,2,7,26,137,923,6261,43228,293991,1993292,13620471,94043892,
%T 656241875
%N Number of n-bead necklaces labeled with numbers -6..6 not allowing reversal, with sum zero and first and second differences in -6..6.
%C Column 6 of A209007.
%e Some solutions for n=6:
%e .-2...-5...-1...-4...-4...-5...-4...-1...-5...-2...-2...-2...-4...-5...-3...-1
%e ..1...-5...-1...-4...-1...-1...-3...-1...-3...-2....1....0...-4...-4...-1....0
%e ..0....1....1...-2....1....4....3....0....1...-1....0....1....2....0...-1....0
%e ..1....5...-1....4....2....5....3....1....5...-1....1....2....2....4....1...-1
%e ..0....4....1....4....3....0....2....1....4....3...-1....0....2....5....3....2
%e ..0....0....1....2...-1...-3...-1....0...-2....3....1...-1....2....0....1....0
%K nonn
%O 1,2
%A _R. H. Hardin_, Mar 04 2012