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%I #11 Mar 19 2018 04:13:08
%S 1,1,3,5,13,46,157,608,2245,8184,30309,113476,428729,1637809,6309489,
%T 24478530,95532067,374703951
%N Number of n-bead necklaces labeled with numbers -3..3 not allowing reversal, with sum zero and first and second differences in -3..3.
%C Column 3 of A209007.
%e Some solutions for n=6:
%e -2 -1 -2 -2 -2 -1 -1 -1 -1 -1 -3 -1 -2 -2 -2 -1
%e -2 -1 0 -2 0 0 0 -1 0 -1 -2 -1 -2 -1 0 0
%e 0 -1 1 0 2 0 1 1 0 0 1 0 1 1 0 0
%e 1 1 2 2 2 0 0 1 -1 0 3 1 1 2 2 1
%e 2 2 0 2 -1 0 0 0 1 1 2 0 1 1 1 0
%e 1 0 -1 0 -1 1 0 0 1 1 -1 1 1 -1 -1 0
%K nonn,more
%O 1,3
%A _R. H. Hardin_, Mar 04 2012