diff --git a/mex/sources/k_order_perturbation/k_ord_dynare.cc b/mex/sources/k_order_perturbation/k_ord_dynare.cc
index cce518db9..ce0b1b855 100644
--- a/mex/sources/k_order_perturbation/k_ord_dynare.cc
+++ b/mex/sources/k_order_perturbation/k_ord_dynare.cc
@@ -211,27 +211,9 @@ KordpDynare::populateDerivativesContainer(const TwoDMatrix &g, int ord, const ve
             s[2] = revOrder[s2];
           else
             s[2] = s2;
-	  // reordering symmetry indices in increasing order
-	  if (s[0] > s[1])
-	    {
-	      int temp = s[0];
-	      s[0] = s[1];
-	      s[1] = temp;
-	    }
-	  if (s[1] > s[2])
-	    {
-	      int temp = s[1];
-	      s[1] = s[2];
-	      s[2] = temp;
-	    }
-	  if (s[0] > s[1])
-	    {
-	      int temp = s[0];
-	      s[0] = s[1];
-	      s[1] = temp;
-	    }
-	  double x = g.get(i, 2);
-	  mdTi->insert(s, j, x);
+          double x = g.get(i, 2);
+          if (s.isSorted())
+            mdTi->insert(s, j, x);
         }
     }
 
diff --git a/preprocessor/DynamicModel.cc b/preprocessor/DynamicModel.cc
index c69bb7ef6..f071edd86 100644
--- a/preprocessor/DynamicModel.cc
+++ b/preprocessor/DynamicModel.cc
@@ -2137,8 +2137,6 @@ DynamicModel::writeDynamicModel(ostream &DynamicOutput, bool use_dll) const
       d3->writeOutput(third_derivatives_output, output_type, temporary_terms);
       third_derivatives_output << ";" << endl;
 
-      k++;
-
       // Compute the column numbers for the 5 other permutations of (id1,id2,id3) and store them in a set (to avoid duplicates if two indexes are equal)
       set<int> cols;
       cols.insert(id1 * hessianColsNbr + id3 * dynJacobianColsNbr + id2);
@@ -2147,7 +2145,7 @@ DynamicModel::writeDynamicModel(ostream &DynamicOutput, bool use_dll) const
       cols.insert(id3 * hessianColsNbr + id1 * dynJacobianColsNbr + id2);
       cols.insert(id3 * hessianColsNbr + id2 * dynJacobianColsNbr + id1);
 
-      int k2 = 0; // Keeps the offset of the permutation relative to k
+      int k2 = 1; // Keeps the offset of the permutation relative to k
       for (set<int>::iterator it2 = cols.begin(); it2 != cols.end(); it2++)
         if (*it2 != ref_col)
           {