How do I find the summation of this series?
28254
Why $\sum_{k=1}^{\infty} \frac{k}{2^k} = 2$?
91316
Sum of the series $\sum _{ r=1 }^{ \infty }{ \frac { { r }^{ 3 } }{ r! } } $
148883
Sum of the series $\frac{1}{2\cdot 4}+\frac{1\cdot3}{2\cdot4\cdot6}+\dots$
31731
How to turn this into an equation and then sum the series?
39659
Is there a closed formula for this summation?
26491
Sum function of a series
76387
Evaluate the series $\sum_{n=1}^{\infty} \frac{2^{[\sqrt{n}]}+2^{-[\sqrt{n}]}}{2^n}$
150355
Finding sum of binomial series
58262
Find the sum of the series $1+\frac{1}{3}\cdot\frac{1}{4}+\frac{1}{5}\cdot\frac{1}{4^2}+\frac{1}{7}\cdot\frac{1}{4^3}+\cdots$
28378
Find the infinite sum of the series $\sum_{n=1}^\infty \frac{1}{n^2 +1}$
115170
What is the formula for this numerical series?
62271
Find the sum of the series: $\cos^3 \alpha +\cos^3 {3\alpha} + \cos^3 {5\alpha}+....+\cos^3 {(2n-1)\alpha}$.
134361
Calculating the sum of a binomial coefficient series
67731
Calculate the sum of infinite series with general term $\frac{n^2}{2^n}$.
155250
Summation Series for fractions
59253
Summing the power series $\sum\limits_{n=0}^\infty (-1)^n \frac{x^{2n+1}}{2n+1}\prod\limits_{k=1}^n\frac{2k-1}{2k} $
123951
Problem calculating sum of convergent series of $\sum_{n=2}^{\infty} \frac{1}{n^{2}-1}$