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%I #8 Apr 11 2022 13:21:05
%S 1,4,12,57,276,1465,8008,45408,263168,1554582,9318412,56549840,
%T 346717662,2144555617,13365472929,83848948043,529091046781,
%U 3355802952070
%N Number of n-bead necklaces labeled with numbers -3..3 not allowing reversal, with sum zero and avoiding the pattern z z+1 z+2.
%C Column 3 of A209073.
%e Some solutions for n=6:
%e .-2...-2...-2...-3...-2...-2...-3...-3...-2...-2...-3...-2...-2...-3...-3...-3
%e ..0...-1....1....2....2....2....3...-1...-2....2....1....3...-1...-3....1....3
%e ..1....3....2....1...-1....0....1....0....3....0....3....1....1....3....1....2
%e .-1....0...-1...-2....3....1....3....3...-1...-2...-1...-1....2....2....0....0
%e ..3...-1....0....3...-1....0...-2...-1....0....3....1....0....1....3...-1...-1
%e .-1....1....0...-1...-1...-1...-2....2....2...-1...-1...-1...-1...-2....2...-1
%Y Cf. A209073.
%K nonn
%O 1,2
%A _R. H. Hardin_, Mar 04 2012
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