Sum: $\sum_{k=1}^{\infty}{2k^2}/{5^{k}}$
7686
How to prove $\sum_{n=0}^{\infty} \frac{n^2}{2^n} = 6$?
145798
Generalizing $\sum \limits_{n=1}^{\infty }n^{2}/x^{n}$ to $\sum \limits_{n=1}^{\infty }n^{p}/x^{n}$
120988
Infinite Series $\sum 1/(n(n+1))$
67271
$\sum_{n=-\infty}^{\infty}\frac{1}{(u +n)^2}=\frac{\pi^2}{(\sin \pi u)^2}$
146651
Evaluting sum $\sum \limits_{n=0}^\infty\frac{n^k}{n!}$
30518
Formula for $\sum_{k=1}^n \frac{1}{k(k+1)(k+2)}$?
9193
Simple series convergence/divergence: $\sum_{k=1}^{\infty}\frac{2^{k}k!}{k^{k}}$
134610
Find the sum of finite series $S=\sum_{k=1}^{2015}{(-1)^{\frac{k(k+1)}{2}}}k$
107789
Sum of $\sum \limits_{n=0}^{\infty} \frac{1}{(kn)!}$
124229
Simplify $\sum_{k=0}^{\infty} x^ky^{\frac{k(k+1)}{2}}$
103833
limit $\lim_{n\to \infty }\sum_{k=1}^{n}\frac{k}{k^2+n^2}$
52987
$\sum_{n=-\infty}^{\infty}\frac{1}{(n+\alpha)^2}=\frac{\pi^2}{(\sin \pi \alpha)^2}$?
117863
Series $\sum_{n=1}^\infty \frac{n^n}{(n!)^2}$
28254
Why $\sum_{k=1}^{\infty} \frac{k}{2^k} = 2$?
102942
Compute the sum $\sum_{k=1}^{\infty}k^mz^k$ where $|z|<1$
57549
Finding the sum $\sum_{k=1}^rk^2\binom {n-k}{r-k}$
101138
Convergent or divergent: $\sum_{k=1}^{\infty}\frac{2^{k}\cdot k!}{k^{k}}$