Number of immersions of an unoriented circle into the unoriented sphere with n double points.
A008989
Number of immersions of an unoriented circle into the unoriented sphere with n double points.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =6a(4) =19a(5) =76a(6) =376a(7) =2194a(8) =14614a(9) =106421a(10) =823832a(11) =6657811a(12) =55557329a(13) =475475046a(14) =4155030702a(15) =36959470662a(16) =333860366236
External references
- oeis: A008989