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Number of n-bead necklaces labeled with numbers -6..6 not allowing reversal, with sum zero with no three beads in a row equal.
0

%I #6 Mar 12 2017 23:24:40

%S 1,7,42,366,3376,33468,344456,3656654,39711890,439202182,4929418548,

%T 56004017042,642825693604

%N Number of n-bead necklaces labeled with numbers -6..6 not allowing reversal, with sum zero with no three beads in a row equal.

%C Column 6 of A208945.

%e Some solutions for n=5:

%e .-4...-4...-3...-5...-4...-2...-3...-6...-6...-6...-4...-5...-3...-4...-2...-5

%e ..2...-3....4....6....6...-1....1....1....1...-3....4....2...-2....4...-1....5

%e ..0....2...-2...-2....3....2....0...-2...-4....1....3...-3...-3....6...-2...-3

%e ..1....1....1...-3...-3...-2...-3....3....4....4....0....0....2...-3...-1...-2

%e ..1....4....0....4...-2....3....5....4....5....4...-3....6....6...-3....6....5

%K nonn

%O 1,2

%A _R. H. Hardin_, Mar 03 2012