A sequence $(x_n)$ satisfying $0\leq x_n \leq \frac{1}{n}$ where $\sum(-1)^n x_n$ diverges

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A sequence $(x_n)$ satisfying $0\leq x_n \leq \frac{1}{n}$ where $\sum(-1)^n x_n$ diverges. This is a HW assignment problem for my undergrad real analysis class. I cannot come up with a sequence that is less than $1/n$ that diverges when summed as an alternating series. Any help would be appreciated

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$$ \text{Let}\;\, \large{{x_n}} = \begin{cases} \small{\displaystyle{\frac{1}{n^2}}} & n \text{ is odd}\\[6pt] \small{\displaystyle{\frac{1}{n}}} & n \text{ is even}\\ \end{cases} $$