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A209484 Number of n-bead necklaces labeled with numbers -7..7 allowing reversal, with sum zero and avoiding the patterns z z+1 z+2 and z z-1 z-2. 0

%I

%S 1,8,31,311,3014,34233,401634,4907310,61316012,780896062,10092511209

%N Number of n-bead necklaces labeled with numbers -7..7 allowing reversal, with sum zero and avoiding the patterns z z+1 z+2 and z z-1 z-2.

%C Column 7 of A209485.

%e Some solutions for n=6:

%e .-7...-6...-7...-7...-5...-7...-5...-5...-5...-7...-6...-7...-6...-5...-6...-4

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

%e ..7....4....4...-4....5....4....2....0...-1....5....3...-3...-2...-1....1...-1

%e .-7....3....0....4...-1....6...-4....0....2...-5...-5....3....1....6...-5...-4

%e ..2...-5....5....1....1....0....1....7....2....7....5....4....7...-2....6....7

%e ..4....3....1....7....5....1....6....1....5....1....3....4....5....4....3....4

%K nonn

%O 1,2

%A _R. H. Hardin_, Mar 09 2012

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Last modified December 7 22:50 EST 2021. Contains 349590 sequences. (Running on oeis4.)