A008984 Number of immersions of the oriented circle into the oriented plane with n double points and index n-1.

1, 1, 3, 10, 35, 133, 538, 2144, 8643, 34690, 139122, 556618

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• nice
• more

References

• V. I. Arnold, Topological Invariants of Plane Curves and Caustics, American Math. Soc., 1994, p. 18.

Crossrefs

Cf. A008980, A008981, A008982, A008983, A008985, A054993.

Extensions

Name corrected by Andrey Zabolotskiy, Oct 22 2023

a(6)-a(11) from Andrey Zabolotskiy, Jan 19 2025