diff --git a/Euler_Problem.ipynb b/Euler_Problem.ipynb
index a2a0372c3e860df8e0565f3379bbcb898b89c267..60433c7cc65c5b6fcef247c497bf3c255d06b4e7 100644
--- a/Euler_Problem.ipynb
+++ b/Euler_Problem.ipynb
@@ -26,7 +26,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 2,
+   "execution_count": 1,
    "metadata": {},
    "outputs": [
     {
@@ -35,7 +35,7 @@
        "Loaded machine: Euler_Problem_067"
       ]
      },
-     "execution_count": 2,
+     "execution_count": 1,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -59,6 +59,9 @@
     "  )\n",
     "  )\n",
     " & OptimalSolution = Sol(1)(1)\n",
+    "ASSERTIONS\n",
+    " OptimalSolution = 7273;\n",
+    " n = 100\n",
     "END"
    ]
   },
@@ -79,7 +82,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 3,
+   "execution_count": 2,
    "metadata": {},
    "outputs": [
     {
@@ -88,7 +91,7 @@
        "Machine constants set up using operation 0: $setup_constants()"
       ]
      },
-     "execution_count": 3,
+     "execution_count": 2,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -99,7 +102,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 4,
+   "execution_count": 3,
    "metadata": {},
    "outputs": [
     {
@@ -108,7 +111,7 @@
        "Machine initialised using operation 1: $initialise_machine()"
       ]
      },
-     "execution_count": 4,
+     "execution_count": 3,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -119,48 +122,29 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 5,
-   "metadata": {},
-   "outputs": [
-    {
-     "data": {
-      "text/markdown": [
-       "$7273$"
-      ],
-      "text/plain": [
-       "7273"
-      ]
-     },
-     "execution_count": 5,
-     "metadata": {},
-     "output_type": "execute_result"
-    }
-   ],
-   "source": [
-    ":eval OptimalSolution"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": 6,
+   "execution_count": 4,
    "metadata": {},
    "outputs": [
     {
      "data": {
       "text/markdown": [
-       "$100$"
+       "|Predicate|Value|\n",
+       "|---|---|\n",
+       "|$\\mathit{OptimalSolution} = 7273$|$\\mathit{TRUE}$|\n",
+       "|$\\mathit{n} = 100$|$\\mathit{TRUE}$|"
       ],
       "text/plain": [
-       "100"
+       "OptimalSolution = 7273 = TRUE\n",
+       "n = 100 = TRUE"
       ]
      },
-     "execution_count": 6,
+     "execution_count": 4,
      "metadata": {},
      "output_type": "execute_result"
     }
    ],
    "source": [
-    ":eval n"
+    ":check assertions"
    ]
   }
  ],