diff --git a/assignments/a4/a4.tex b/assignments/a4/a4.tex
index df5eb61..15fba23 100644
--- a/assignments/a4/a4.tex
+++ b/assignments/a4/a4.tex
@@ -263,8 +263,10 @@ The loop in the function runs until $N[-2] + 6 < n$. Since $N = \text{list}[1, 5
 
 Since the loop contained only constant-time operations, the runtime of the loop is $\cO(n)$.
 
-\item[2.]
-TODO: Running-time analysis of \texttt{starting\_coprime\_numbers}.
+Since there are only constant-time operations outside the loop, the runtime of the entire function is $\cO(n)$.
+
+\item[2.] 
+Running-time analysis of \texttt{starting\_coprime\_numbers}.
 
 \item[3.]
 TODO: Running-time analysis of \texttt{coprime\_to\_all}.