Prove that the power series for e^z does not converge uniformly on C.

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SUMMARY

The power series for e^z, represented as e^z = ∑(k=0 to ∞) z^k/k!, does not converge uniformly on the complex plane C. The discussion highlights a key proposition: if f_n is a sequence of entire functions converging uniformly to 0 on C, then f_n must be eventually constant. The user successfully proved this proposition using uniform convergence and Liouville's theorem but struggled to apply it to demonstrate the non-uniform convergence of the power series for e^z.

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michael.wes
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Homework Statement



Prove that the power series for e^z does not converge uniformly on C.


Homework Equations



[tex]e^z=\sum_{k=0}^\infty z^k/k![/tex]

The Attempt at a Solution



The hint in the problem is to prove a proposition first:

If f_n is a sequence of entire functions that converges to 0 uniformly on C, then the f_n are eventually constant.

I proved this (an easy application of uniform convergence and Liouville's theorem), but I don't see how to use this to prove the main question.

Thanks for your help!
MW
 
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Take the f_n to be the partial sums of the power series of e^z.
 

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