Question 120
A restricted path of length $n$ is a path of length $n$ such that for all $i$ between $1$ and $n-2$ inclusive, if the $i$th step is upward, the $i+1$st step must be rightward.
Find the number of restricted paths that start at $(0,0)$ and end at $(7,3)$.
Find the number of restricted paths that start at $(0,0)$ and end at $(7,3)$.