Let $\Delta$ be the operator $\sum_{j = 1}^n \frac{\partial^2}{\partial x_j^2}$. Let $s$ be a positive integer. Then it follows from Theorem 7.1.22 in Hormander's book that $(- \Delta)^s$ has a parametrix $E$. Parametrix is defined to be a distribution such that $$ (-\Delta)^s E = \delta + \omega $$ for some $\omega$, a $C^{\infty}$ function in $\mathbb{R}^n$. Theorem 7.1.22 further states that $E$ is a $C^{\infty}$ function in $\mathbb{R}^n \setminus \{0\}$.
Apparently this $E$ is supported in the open unit ball... This is stated during the proof of Lemma 7.6.3 which I am trying to go through. If someone could give me a hint on how I can see this, it would be appreciated!