Pattern: 1/1, 2/1, 1/2, 1/3, 2/2, 3/1, 4/1, 3/2, ...

With the fraction A/B:

• When A is 1 for the first time, increase B once more. Then A goes up and B goes down from there.
• When B is 1 for the first time, increase A once more. Then B goes up and A goes down from there.