Number of n-bead necklaces of 5 colors allowing reversal, with no adjacent beads having the same color.

A208541

Number of n-bead necklaces of 5 colors allowing reversal, with no adjacent beads having the same color.

Terms

    a(0) =5a(1) =10a(2) =10a(3) =55a(4) =102a(5) =430a(6) =1170a(7) =4435a(8) =14570a(9) =53764a(10) =190650a(11) =704370a(12) =2581110a(13) =9608050a(14) =35791470a(15) =134301715a(16) =505290270a(17) =1909209550a(18) =7233629130a(19) =27489127708a(20) =104715393910a(21) =399827748310

External references