Number of pairs of orientable necklaces with n beads and up to 5 colors; i.e., turning the necklace over does not leave it unchanged. The turned-over necklace is not included in the count.
A278641
Number of pairs of orientable necklaces with n beads and up to 5 colors; i.e., turning the necklace over does not leave it unchanged. The turned-over necklace is not included in the count.
Terms
- a(0) =0a(1) =0a(2) =0a(3) =10a(4) =45a(5) =252a(6) =1130a(7) =5270a(8) =23520a(9) =106960a(10) =483756a(11) =2211650a(12) =10149805a(13) =46911060a(14) =217868310a(15) =1017057518a(16) =4767797895a(17) =22438419120a(18) =105960938380a(19) =501928967930
External references
- oeis: A278641