Number of primitive (period n) n-bead necklaces with exactly four different colored beads.

A056289

Number of primitive (period n) n-bead necklaces with exactly four different colored beads.

Terms

    a(0) =0a(1) =0a(2) =0a(3) =6a(4) =48a(5) =260a(6) =1200a(7) =5100a(8) =20720a(9) =81828a(10) =318000a(11) =1222870a(12) =4675440a(13) =17813820a(14) =67769504a(15) =257695800a(16) =980240880a(17) =3731732200a(18) =14222737200a(19) =54278498154a(20) =207438936800a(21) =793940157900

External references