Thank you Henry.

src/measure/measurable-maps/product.tex

@@ -42,7 +42,7 @@
     Let $\seqf{X_j}$ be topological spaces, $X = \prod_{j = 1}^n X_j$, then:
     \begin{enumerate}
         \item $\bigotimes_{j = 1}^n \cb_{X_j} \subset \cb_{X}$.
-        \item If $\seq{X_j}$ are separable, then $\bigotimes_{j = 1}^n \cb_{X_j} = \cb_{X}$
+        \item If $\seqf{X_j}$ are separable, then $\bigotimes_{j = 1}^n \cb_{X_j} = \cb_{X}$
     \end{enumerate}
 \end{proposition}
 \begin{proof}