Crosscap number two alternaitng knots
In this talk, we determine the set of alternating knots with crosscap
number two. To obtain it, we give an upper bound of the crosscap
number. In the case of the crosscsp number two alternating knots,
the bound implies the equality.
This is a joint work with Yusuke Takimura (Gakushuin Boys' Junior High School).