Number of n-bead necklace structures with beads of exactly three colors and no adjacent beads having the same color.
A327397
Number of n-bead necklace structures with beads of exactly three colors and no adjacent beads having the same color.
Terms
- a(0) =0a(1) =0a(2) =1a(3) =1a(4) =1a(5) =3a(6) =3a(7) =7a(8) =11a(9) =19a(10) =31a(11) =63a(12) =105a(13) =201a(14) =367a(15) =695a(16) =1285a(17) =2451a(18) =4599a(19) =8775a(20) =16651a(21) =31837a(22) =60787a(23) =116639a(24) =223697a(25) =430395a(26) =828525a(27) =1598227a(28) =3085465a(29) =5965999
External references
- oeis: A327397