Have I simplified this integral correctly?

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I was trying to evaluate this integral for $n\in \Bbb R:$

$$ I_n=\int_0^n ne^{\frac{1}{\log(x/n)}}~dx$$

But I could not find a way (except for $n=1$). Wolfram Alpha found a closed form for $n=1$ but failed to find any other closed forms.

Then I observed that the integral could be simplified to:

$$I_n=n^2\int_0^1 e^{\frac{1}{\log(x)}}~dx $$

And so $I_n$ is a parabola multiplied by a constant, and a closed form is found.

Is my simplification step valid?

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Your simplification is correct, which follows from substituting $u=\frac xn$, $dx=ndu$.