STABLE DOUBLE POINT NUMBERS OF PAIRS OF SPHERICAL CURVES
For a pair of spherical curves P and we introduce a quantity called the stable double point number of P and denoted A trivial spherical curve is a spherical curve with no double point, denoted O. In this paper, we prove two results relevant to the question whether holds or not, where denotes the double point number. One is a positive result. Concretely speaking, we show that each 2-bridge spherical curve denoted satisfies The other is a negative result. Concretely speaking, we show that the pretzel spherical curve denoted satisfies
spherical curve, double point number, 2-bridge spherical curve, pretzel spherical curve.