Number of knot diagrams of type 1PI with n crossings and two outgoing strings.
A067647
Number of knot diagrams of type 1PI with n crossings and two outgoing strings.
Terms
- a(0) =0a(1) =2a(2) =4a(3) =18a(4) =108a(5) =748a(6) =5648a(7) =45234a(8) =378300a(9) =3271204a(10) =29049824a(11) =263656356a(12) =2436827328a(13) =22871937208a(14) =217536523260
External references
- oeis: A067647