diff --git a/chapter13.tex b/chapter13.tex
index f318a98..a888434 100644
--- a/chapter13.tex
+++ b/chapter13.tex
@@ -53,7 +53,7 @@ \subsubsection{Example}
 \node[draw, circle] (2) at (4,3) {2};
 \node[draw, circle] (3) at (1,1) {3};
 \node[draw, circle] (4) at (4,1) {4};
-\node[draw, circle] (5) at (6,2) {6};
+\node[draw, circle] (5) at (6,2) {5};
 \node[color=red] at (1,3+0.55) {$0$};
 \node[color=red] at (4,3+0.55) {$\infty$};
 \node[color=red] at (1,1-0.55) {$\infty$};