A268572 Number of bicolored immersions of unoriented circle into oriented sphere with n double points and no simple loop.
0, 0, 2, 1, 4, 9, 38, 133, 640, 2864
Offset: 1
Links
- Robert Coquereaux and Jean-Bernard Zuber, Maps, immersions and permutations, Journal of Knot Theory and Its Ramifications, Vol. 25, No. 8 (2016), 1650047; arXiv preprint, arXiv:1507.03163 [math.CO], 2015-2016. See Table 6.
Formula
Extensions
Name clarified by Andrey Zabolotskiy, Jun 08 2024