Take the 2-minute tour ×
Mathematics Stack Exchange is a question and answer site for people studying math at any level and professionals in related fields. It's 100% free, no registration required.

Prove that there is no function $f$ on the open unit disk, defined by a convergent power series, such that $f(1/n)=(-1)^n/n^2$.

I'm not sure how to start... any hints would be appreciated!

share|improve this question

1 Answer 1

Hint: Let $g(z) = z^2$ and look at points where $f(z) = g(z)$.

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.