Calculate the value of the sum $1+3+5+\cdots+(2n+1)$
17491
Proof by Induction: Solving $1+3+5+\cdots+(2n-1)$
95786
Sum $\frac{1}{6} + \frac{5}{6\cdot 12} + \frac{5\cdot 8}{6\cdot 12\cdot 18} + \frac{5\cdot 8\cdot 11}{6\cdot 12\cdot 18\cdot 24}+\ldots$
126105
Compute $\sum_{k=1}^{n} \frac 1 {k(k + 1)} $
141357
Is $1+2+3+4+\cdots=-\frac{1}{12}$ the unique ''value'' of this series?
91933
Evaluate $\sum_{k=1}^nk\cdot k!$
138172
Find the sum to n terms of the series $\frac{1}{1.2.3}+\frac{3}{2.3.4}+\frac{5}{3.4.5}+\frac{7}{4.5.6}+\cdots$..
13085
Evaluate $ 1 + \frac{1}{3}\frac{1}{4}+\frac{1}{5}\frac{1}{4^2}+\frac{1}{7}\frac{1}{4^3}+\dots$
147635
Find the sum $\frac{1}{2\cdot 3}+\frac{1}{3\cdot 4}+\dots+\frac{1}{99\cdot 100}$
57780
$\sum_{i=1}^n i\cdot i! = (n+1)!-1$ By Induction
7302
$\sum k! = 1! +2! +3! + \cdots + n!$ ,is there a generic formula for this?
37007
Evaluating $\sum_{k=1}^{n} \frac{1}{k(k+1)}$
103840
Calculate $\sum_{k=1}^n k2^{n-k}$
48200
Simplify $\sum_{i=0}^n (i+1)\binom ni$
94143
Evaluate:: $ 2 \sum_{n=1}^\infty \frac{(-1)^{n+1}}{n+1}\left( 1 + \frac12 +\cdots + \frac 1n\right) $
29524
Formula for the sum $\sum_{i=2}^{n} \frac1{i^2-1}$
3798
Finding formula for sum $S_n = \sum_{i=1}^n i(i-1)$
74120
Find the value of $\sum_{n=1}^{\infty} \frac{2}{n}-\frac{4}{2n+1}$