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%I #6 Mar 13 2017 00:15:26
%S 1,4,15,95,683,5404,44209,371893,3189719,27799922,245493567,
%T 2192108831,19760508059,179591215329
%N Number of n-bead necklaces labeled with numbers -6..6 not allowing reversal, with sum zero and first differences in -6..6.
%C Column 6 of A208993.
%e Some solutions for n=6:
%e .-3...-5...-3...-6...-3...-6...-4...-4...-5...-4...-4...-5...-3...-2...-3...-3
%e .-1....0....2...-3....0...-4...-4....1...-2...-1...-1...-1...-1...-2...-1....0
%e .-2....2...-3....2...-1...-1...-1....4...-2....1....4...-1....3....1....4....0
%e ..2....1....2....5....4....5....4...-1....4....4....2....3....4...-1...-1...-3
%e ..1....3....0....4....2....6....5....1....5...-2....0....5...-1....0....1....3
%e ..3...-1....2...-2...-2....0....0...-1....0....2...-1...-1...-2....4....0....3
%K nonn
%O 1,2
%A _R. H. Hardin_, Mar 04 2012
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