Number of primitive (period n) bracelet structures using a maximum of four different colored beads.

A056363

Number of primitive (period n) bracelet structures using a maximum of four different colored beads.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =2a(4) =5a(5) =10a(6) =29a(7) =72a(8) =230a(9) =700a(10) =2421a(11) =8308a(12) =30070a(13) =108990a(14) =403188a(15) =1497057a(16) =5607200a(17) =21076570a(18) =79595257a(19) =301492044a(20) =1145558141a(21) =4363503609a(22) =16660196142a(23) =63741248200a(24) =244339616370a(25) =938255682540

External references