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%I #6 Mar 13 2017 00:14:52
%S 1,4,19,144,1207,11010,104001,1008880,9979817,100308712,1021569027,
%T 10520123630,109367955653
%N Number of n-bead necklaces labeled with numbers -7..7 not allowing reversal, with sum zero and first differences in -7..7.
%C Column 7 of A208993.
%e Some solutions for n=6:
%e .-4...-6...-3...-7...-6...-3...-3...-5...-7...-4...-5...-2...-6...-4...-5...-7
%e .-1...-2....0....0....1....0....4....1...-2....3....0....3....1....2...-2...-2
%e ..0....3....0....4....6...-2...-2....1....0....2....4...-1....5...-1...-2....5
%e ..3....1...-2....4....3....4...-2...-1....6....3...-1....0...-2....2....4...-1
%e .-1....5....5...-1...-1....2....3....2....5...-3....2....1....3....3....5....5
%e ..3...-1....0....0...-3...-1....0....2...-2...-1....0...-1...-1...-2....0....0
%K nonn
%O 1,2
%A _R. H. Hardin_, Mar 04 2012