diff --git a/src/sage/sets/recursively_enumerated_set.pyx b/src/sage/sets/recursively_enumerated_set.pyx
index 08ab505a4e7..e40bf792f43 100644
--- a/src/sage/sets/recursively_enumerated_set.pyx
+++ b/src/sage/sets/recursively_enumerated_set.pyx
@@ -180,11 +180,11 @@ classes being very similar):
         \begin{array}{ccc}
              \swarrow & \downarrow & \searrow \\
                 ``aa" & ``ab" & ``ac" \\
-        \end{array}   & 
+        \end{array}   &
         \begin{array}{ccc}
              \swarrow & \downarrow & \searrow \\
                 ``ba" & ``bb" & ``bc" \\
-        \end{array}   & 
+        \end{array}   &
         \begin{array}{ccc}
              \swarrow & \downarrow & \searrow \\
                 ``ca" & ``cb" & ``cc" \\