Binomial coefficients / sums
113290
Prove combinatorics identity
132249
Sum of every $k$th binomial coefficient.
143945
Summation of combination of binomial coefficient
22948
Is this binomial coefficient identity known?
150438
Binomial theorem for non integers ? O_o ??
64803
Counting two ways, $\sum \binom{n}{k} \binom{m}{n-k} = \binom{n+m}{n}$
107810
Induction with Binomial Coefficients
125148
Summation of series $\sum_{k=0}^\infty 2^k/\binom{2k+1}{k}$
112253
How to find sums like $\sum_{k=0}^{39} \binom{200}{5k}$
87589
Evaluate $\binom{n}{0}+\binom{n}{2}+\binom{n}{4}+...+\binom{n}{2k}$
115686
A finite summation of double binomial coefficients
57549
Finding the sum $\sum_{k=1}^rk^2\binom {n-k}{r-k}$
59638
How to prove this result on binomial coefficients?
104704
Evaluate $\sum\limits_{k=0}^n \binom{n}{k}$ combinatorially
61270
Binomial Theorem Sum
28027
Find $\sum_{k=0}^{n}4^k \binom{n}{k}$
11612
How to show that $\sum_{k=1}^n k(n+1-k)=\binom{n+2}3$?