Number of isomorphism classes of connected 3-regular (trivalent, cubic) loopless multigraphs of order 2n.
A000421
Number of isomorphism classes of connected 3-regular (trivalent, cubic) loopless multigraphs of order 2n.
Terms
- a(0) =1a(1) =2a(2) =6a(3) =20a(4) =91a(5) =509a(6) =3608a(7) =31856a(8) =340416a(9) =4269971a(10) =61133757a(11) =978098997a(12) =17228295555a(13) =330552900516
External references
- oeis: A000421