Evaluating $\sum_{k=0}^{n}{n+k\choose n}\frac{1}{2^{k}}$
14239
How to show $\sum_{k=0}^{n}\binom{n+k}{k}\frac{1}{2^k}=2^{n}$
121661
Evaluating the sum $\Sigma \, \frac{1}{k(k+p)}$
30518
Formula for $\sum_{k=1}^n \frac{1}{k(k+1)(k+2)}$?
120976
Proving $\sum_{k=0}^{n}k{n\choose k}^2 = n{2n-1 \choose n-1} $
114280
Computing $\sum_{n=1}^∞\frac{1}{(n+1)(n+2)(n+3)....(n+p)}$
5054
Calculate $\sum\limits_{k=0}^{\infty}\frac{1}{{2k \choose k}}$
58428
Proving $\sum_{k=0}^{n} {k \choose a} {n-k \choose b} = {n+1\choose a+b+1}$
138542
Evaluating sums question $\sum_{k=2}^n \frac{1}{k^2-1}$
115236
Calculate the sum of inverse values of ${n\choose 0}, {n\choose 1}, ... {n\choose n}$
6416
How can I evaluate $\sum_{n=0}^\infty(n+1)x^n$?
68080
Evaluation of $\sum_{k=0}^n{n\choose k}^2u^k$
326
Find $\sum_{k=1}^{\infty}\frac{1}{2^{k+1}-1}$
55061
Evaluating the sum after reordering an infinite series $1-\frac {1} {2}+\frac {1} {3}-\frac {1} {4}+\ldots $
87589
Evaluate $\binom{n}{0}+\binom{n}{2}+\binom{n}{4}+...+\binom{n}{2k}$
17638
Sum with binomial coefficients: $\sum_{k=0}^{n}{2n\choose 2k}$
103840
Calculate $\sum_{k=1}^n k2^{n-k}$
43509
Evaluating $\sum_{n=1}^{\infty}\frac{(n-1)!}{\prod_{r=1}^{n}(x+r)}$ for $x\in\mathbb{R}^{+}$