How to find the sum that are not geometric series or telescoping series?
57759
Determining the infinite sum $\sum\limits_{n=0}^{\infty}\frac{(-1)^n}{2n+1}$
113633
sum of series using mean value theorem
121554
Finding $\sum\frac{1}{2^n(n+1)}$
84181
Is there a cleaner proof of convergence for this almost-telescoping series
94902
Simplifying a geometric sum
141978
How to find the infinite sum
65653
Find a closed form of the series $\sum_{n=0}^{\infty} n^2x^n$
55061
Evaluating the sum after reordering an infinite series $1-\frac {1} {2}+\frac {1} {3}-\frac {1} {4}+\ldots $
91316
Sum of the series $\sum _{ r=1 }^{ \infty }{ \frac { { r }^{ 3 } }{ r! } } $
29170
Find the sum of the series $\sum \frac{1}{n(n+1)(n+2)}$
148970
How to calculate such sums of Legendre symbols?
150355
Finding sum of binomial series
45588
Summing a series with a changing power
26908
Partial Sums of Geometric Series
4573
Explicitly finding the sum of $\arctan(1/(n^2+n+1))$
134610
Find the sum of finite series $S=\sum_{k=1}^{2015}{(-1)^{\frac{k(k+1)}{2}}}k$
25504
How to find sum of the infinite series $\sum_{n=1}^{\infty} \frac{1}{ n(2n+1)}$