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I multiplied two series $\displaystyle \sum_{n=1}^{\infty} (-1)^{n} \frac{1}{n^{\frac{3}{4}}}$ and $\displaystyle \sum_{n=1}^{\infty} (-1)^{n} \frac{1}{n^{\frac{1}{4}}}$. I got $\displaystyle 1 + \frac{1}{2^{\frac{3}{4}}2^{\frac{1}{4}}}+\cdots$ I don't know how to write it with symbols so that I could investigate whether it's convergent or not. I'd be thankful for your help!

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