Number of immersions of the unoriented circle into the oriented plane with n double points.
A008981
Number of immersions of the unoriented circle into the oriented plane with n double points.
Terms
- a(0) =1a(1) =2a(2) =5a(3) =21a(4) =102a(5) =639a(6) =4492a(7) =34032a(8) =272252a(9) =2267905a(10) =19502386a(11) =172111844a(12) =1551948268
External references
- oeis: A008981