How to avoid the erf(x)?

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I need to solve the following integral:

$$x\int\frac{e^{\frac{-x^2}{2}}}{x^2}\,dx$$

I'm told that by using the Taylor expansion of $e^z$ and "integrating term by term" show that it's equal to:

$$\alpha x + \sum_{n=0}^{\infty}\frac{(-1)^n}{2^n(2n-1)n!}x^{2n}.$$

Really not sure what to do.