Question 4
Determine all pairs $(h,s)$ of positive integers with the following property. If one draws $h$ horizontal lines and another $s$ lines such that (i) they are not horizontal, (ii) no two of them are parallel, and (iii) no three of the $h+s$ lines are concurrent, then the number of regions formed is $1992$.
The diagram is a small schematic example of the line conditions.
The diagram is a small schematic example of the line conditions.