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Suppose you want to compute the sum $\sum_{n=0}^{\infty} a_n $ You could consider the expression $f(x) = \sum_{n=0}^{\infty} e^{a_n x}$ and try to compute the coefficient of an $x^1$ term in the ...

As an initial note, let me show by example what I mean by the terminology 'residue at $\infty$' I use in the title. I assume there is some standard terminology for this stuff, so I'd appreciate it if ...

So I was considering the divergent everywhere but 0 power series $$ f(x) = \sum_{n=0}^{\infty} e^{e^n} x^n $$ Now one can do the following "questionable" manipulation $$ f(x) = \sum_{n=0}^{\...