Calculate $\sum_{i=0}^{n-1}H_i\cdot i$
108461
Sum of Harmonic Numbers
114911
Evaluate $\sum_{k = 0}^{n} {n\choose k} k^m$
18814
Sum of the series $1+\frac{1\cdot 3}{6}+\frac{1\cdot3\cdot5}{6\cdot8}+\cdots$
112374
Evaluate $ \binom{n}{0}+\binom{n}{2}+\binom{n}{4}+\cdots+\binom{n}{2k}+\cdots$
145048
Prove $\sum_{k = 0}^{n}(-1)^{n - k} \binom{n}{k} \cdot k^n = n!$ and $\sum_{k = 0}^{n}(-1)^{n - k} \binom{n}{k} \cdot k^m = 0$
98808
Finite Sum $\sum_{i=1}^n\frac i {2^i}$
151757
Simplify $\sum_{i=0}^{N/2}{N-i\choose i}$
98933
Calculating the sum of $f(x) = \sum_{n=0}^{\infty} {n \cdot 2^n \cdot x^n}$
562
Formula for calculating $\sum_{n=0}^{m}nr^n$
4253
How to calculate: $\sum_{n=1}^{\infty} n a^n$
92704
Prove that $\sum_{k=1}^{n}k\binom{n}{k}=n\cdot2^{n-1}$
33986
Calculate $\sum_{n=1}^{\infty}(\frac{1}{2n}-\frac{1}{n+1}+\frac{1}{2n+4})$
127150
Finding general formula of $\sum_{i=0}^n i^2 \binom{n}{i}$
99420
Compute $\sum_{n=1}^\infty \frac{1}{(n+1)\sqrt[]{n}+n\sqrt[]{n+1}}$
101017
What is the sum of $\sum\limits_{i=1}^{n}ip^i$?
135927
Calculating $\sum_{n=1}^\infty\frac{1}{(n-1)!(n+1)}$
40784
$\sum_{k=m}^{n}(-1)^k\binom{n}{k}\binom{k}{m}=0, n>m\geq 0$