diff --git a/src/net/sourceforge/plantuml/math/ASCIIMathTeXImg.java b/src/net/sourceforge/plantuml/math/ASCIIMathTeXImg.java
index 7a23f2667..d4d32969b 100644
--- a/src/net/sourceforge/plantuml/math/ASCIIMathTeXImg.java
+++ b/src/net/sourceforge/plantuml/math/ASCIIMathTeXImg.java
@@ -905,8 +905,8 @@ public class ASCIIMathTeXImg {
 										subarr = new ArrayList<String>(Arrays.asList(
 												newFrag.substring(pos.get(i) + 8, subpos.get(pos.get(i)).get(1))));
 										for (int j = 2; j < subpos.get(pos.get(i)).size(); j++) {
-											subarr.add(newFrag.substring(subpos.get(i).get(j - 1) + 1,
-													subpos.get(i).get(j)));
+											subarr.add(newFrag.substring(subpos.get(pos.get(i)).get(j - 1) + 1,
+													subpos.get(pos.get(i)).get(j)));
 										}
 										subarr.add(newFrag.substring(
 												subpos.get(pos.get(i)).get(subpos.get(pos.get(i)).size() - 1) + 1,
diff --git a/test/net/sourceforge/plantuml/math/MathTest.java b/test/net/sourceforge/plantuml/math/MathTest.java
index d649d9c77..391ff41d6 100644
--- a/test/net/sourceforge/plantuml/math/MathTest.java
+++ b/test/net/sourceforge/plantuml/math/MathTest.java
@@ -17,6 +17,9 @@ class MathTest {
 			" '[[a,b],[c,d]]',              {\\left[\\begin{matrix}{a}&{b}\\\\{c}&{d}\\end{matrix}\\right]} ",
 			" color(red)(x),                {\\textcolor{red}{{x}}} ",
 			" color(red)(t)=color(blue)(x), {\\textcolor{red}{{t}}}={\\textcolor{blue}{{x}}} ",
+			" f,                            {f} ",
+			" f_g,                          {{f}_{{g}}} ",
+			" '[[1,2,3],[4,5,6]]',          {\\left[\\begin{matrix}{1}&{2}&{3}\\\\{4}&{5}&{6}\\end{matrix}\\right]} ",
 	})
 	public void testMath(String input, String expected) {
 		final String res = new ASCIIMathTeXImg().getTeX(input);