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%I #6 Mar 12 2017 23:30:45
%S 1,5,12,72,390,2606,17771,128598,950292,7180767,55056590,427567892,
%T 3354737555,26555548849
%N Number of n-bead necklaces labeled with numbers -4..4 allowing reversal, with sum zero and avoiding the patterns z z+1 z+2 and z z-1 z-2.
%C Column 4 of A209485.
%e Some solutions for n=7:
%e .-3...-4...-3...-4...-3...-4...-4...-3...-2...-4...-4...-3...-2...-4...-3...-1
%e .-2...-2...-2...-3...-1...-1....1...-1...-2....2....2...-3...-2....2....2...-1
%e ..4....3....4....0....0....4....1....4...-2...-4....1...-2....1....1...-2...-1
%e ..0....1....2....4....3...-3...-1...-2....0....3...-2....0...-2...-3....2....0
%e .-1...-1...-2....2....2....1....1...-1....2...-4....2....3...-1...-2....0....0
%e ..3...-1....0...-1...-2....2....1...-1....1....3...-2....2....2....3...-1...-1
%e .-1....4....1....2....1....1....1....4....3....4....3....3....4....3....2....4
%K nonn
%O 1,2
%A _R. H. Hardin_, Mar 09 2012
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