For what values of $z$ is $$\sum_{n=0}^\infty\frac{z^n}{1+z^{2n}}$$ convergent?
I tried using the root test, and cannot proceed after obtaining $$\frac{1}{R} = \left|z\right| \text{limsup} \frac{1}{\sqrt{\left|1+z^{2n}\right|}}$$
2026-03-24 22:07:38.1774390058
For what values of $z$ is $\sum_{n=0}^\infty\frac{z^n}{1+z^{2n}}$ convergent?
90 Views Asked by Bumbble Comm https://math.techqa.club/user/bumbble-comm/detail AtRelated Questions in COMPLEX-ANALYSIS
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