Number of n-bead necklaces labeled with numbers -6..6 allowing reversal, with sum zero and first differences in -6..6.
A209030
Number of n-bead necklaces labeled with numbers -6..6 allowing reversal, with sum zero and first differences in -6..6.
Terms
- a(0) =1a(1) =4a(2) =10a(3) =60a(4) =358a(5) =2798a(6) =22249a(7) =186765a(8) =1596162a(9) =13907330a(10) =122758794a(11) =1096122478a(12) =9880366438a(13) =89796245827a(14) =821927851286
External references
- oeis: A209030