Evaluating the Gaussian-like integrals $\int dx\, x^{-n} \exp(-(x-b)^2)$

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Is there a known form for indefinite Gaussian integrals of the form

$$\int dx\, x^{-n}\exp(-(x-b)^2) $$

where $n$ is a positive integer and $b$ is some constant? Mathematica cannot solve integrals of this type, and for some reason I cannot find any terms like this in any integral tables.

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Functions like these tend not to have antiderivatives expressible in closed form in terms of elementary functions.

In the special case $b = 0$, we can write antiderivatives of these functions in terms of the exponential integral $$\operatorname{Ei}_1(x) := \int_1^\infty t^{-1} \exp(-t x) \,dt$$ (for odd $n$) and the error function, $$\operatorname{erf}(x) := \frac{2}{\sqrt\pi} \int_0^x \exp(-t^2) \,dt$$ (for even $n$), but that doesn't provide much insight in the sense that those functions are defined as antiderivatives of functions similar to those in the question.

The first few values are: $$\begin{array}{cc} n & \displaystyle{\int x^{-n} \exp(-x^2) \,dx} \\ \hline 1 & -\frac{1}{2}\operatorname{Ei}_1(x^2) + C\\ 2 & x^{-1} \exp(-x^2) - \sqrt{\pi}\operatorname{erf}(x) + C \\ 3 & \frac{1}{2} \left[-x^{-3} \exp(-x^2) + \operatorname{Ei}_1(x^2)\right] + C \end{array} .$$