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Consider a map $\psi:\Bbb R^2\to \Bbb R^2_+$ with $\psi(x,y)=(e^x,e^y).$ Looking at $\varphi(x)=e^{\frac{1}{\log(x)}}$ we see that it's related to $h(x)=\frac{1}{x}$ via $u=\log(x)$ and $v=\log(\varphi),$ yielding $uv=1.$

I'll try to describe a process:

$(1)$ Change the coordinate system of the plane with $\psi$.

$(2)$ Use a substituition $n\mapsto n^s.$

$(3)$ Sum the resultant function in the new coordinate system.

$(4)$ Find the analytic continuation of the resultant function.

Here's what this looks like in an example:

I started with $h(x)=\frac{1}{x},$ changed the coordinate system and got the new related function $\varphi(x).$ Next I did $n\mapsto n^s$ and then I summed, $\Phi(s)=\sum_{n=1}^\infty e^{-n^s}$ and finally asked about its analytic continuation.

With the help of user @metamorphy an analytic continuation was found

$$\Phi(s)=\Gamma\left(1+\frac1s\right)+\sum_{n=0}^\infty\frac{(-1)^n}{n!}\zeta(-ns).$$See this question.

Is there a simpler example (a cleaner analytic continuation) someone can share using this process?

Is there something I can Google to read more about such a process?

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