trying to fix a doc latex issue

Author: darioizzo

doc/notebooks/map_inversion.ipynb

@@ -305,6 +305,7 @@
     "\\end{array}\n",
     "\\right.\n",
     "$$\n",
+    "\n",
     "with the added initial condition $e(t=0) = e(x_0, y_0, v_{x_0}, v_{y_0})$. We integrate this system up to $t=1$, as we now consider the actual integration time as an ODE parameter. Note that we also added one equation which will track the event value along the dynamics.\n",
     "\n",
     "Using this augmented system of equations we build a variational integrator so that all high orders variations, including the ones w.r.t. $T$ will be computed:\n"