I don't like this problem

Hi there! I'm working on some practice problems in my workbook for a class, and I came across this problem:

 

Let f(x) return the number of times n appears in Pascal's Triangle. For example,(3)=2  and f(4)=2. If n is a positive integer, what is the minimum value of n ?

 

But I cannot seem to get the write answer out of it. Every time I submit an answer it's wrong. Please help! Tysm!