Number of n-bead necklaces labeled with numbers -4..4 allowing reversal, with sum zero and first and second differences in -4..4.
A208966
Number of n-bead necklaces labeled with numbers -4..4 allowing reversal, with sum zero and first and second differences in -4..4.
Terms
- a(0) =1a(1) =2a(2) =2a(3) =8a(4) =19a(5) =90a(6) =371a(7) =1755a(8) =8092a(9) =37970a(10) =179133a(11) =857902a(12) =4152036a(13) =20313811a(14) =100217735a(15) =497983883a(16) =2488970462a(17) =12503041095a(18) =63083893996a(19) =319545209584
External references
- oeis: A208966