TITLE: Evaluating $\sum\limits_{n=1}^{\infty} \left(\frac{1}{4 n-3}+\frac{1}{4 n-1}-\frac{1}{2 n}\right)$
QUESTION [6 upvotes]: $$\sum\limits_{n=1}^{\infty} \left(\frac{1}{4 n-3}+\frac{1}{4 n-1}-\frac{1}{2 n}\right) = \;?$$

I have been trying to see if it can be written as sum of two telescope terms but it looks tricky. Any help ?

REPLY [4 votes]: $$\sum\limits_{n=1}^k \left(\frac{1}{4 n-3}+\frac{1}{4 n-1}-\frac{1}{2 n}\right) =1-\frac12+\frac13-\frac14+\cdots-\frac{1}{2k} + \sum\limits_{n=k}^{2k-1} \frac{1}{2n+1}$$
Can you evaluate the limits of the two series on the right-hand side?