Find a closed formula for $\sum_{n=1}^\infty nx^{n-1}$
72502
Evaluate $\sum_{n=1}^\infty nx^{n-1}$
57759
Determining the infinite sum $\sum\limits_{n=0}^{\infty}\frac{(-1)^n}{2n+1}$
59485
Infinite Series: $\sum_{n=1}^\infty \frac{1}{2^nn}$
93837
How to compute infinite series $\sum_{n=0}^{\infty} ne^{-n}$
150563
Find the sum $\sum_{n=1}^{\infty} \frac{\ln n}{n(n- \ln n)}$
49982
Closed expression for infinite series
55339
Find the sum $\sum_{n=1}^{\infty}\frac{ 1}{n^{2}(2n-1)}$
24373
Hint on computing the series $\sum_{n=2}^\infty \frac{1}{n^2-1}$.
137249
find $\sum_{k=2}^{\infty}\frac{1}{k^2-1}$
141390
Closed form for $\sum_{n=-\infty}^\infty \frac{1}{(z+n)^2+a^2}$
91784
Calculating $\sum_{n=1}^\infty {\frac{1}{2^nn(3n-1)}}$
99843
How to simplify $ \sum_{k=0}^{\infty} \binom{k + r - 1}{k} x^k$
152802
How find series $\sum_{n=1}^{\infty}\frac{(-1)^{[\sqrt[m]{n}]}}{n^a}$?
124229
Simplify $\sum_{k=0}^{\infty} x^ky^{\frac{k(k+1)}{2}}$
54661
How to find the sum $\sum\limits_{n=1}^{\infty}\frac{1}{n!(n^4+n^2+1)}$
122236
How to compute the series: $\sum_{n=0}^{\infty} (-1)^{n-1}\binom{1/2}{n}$
142985
Finding sum of series $\sum^{\infty}_{k=0}\frac{(k+1)(k+2)}{2^k}$