How to sum binomial coefficients which are multiples of 3?
39199
closed form for $\binom{n}{0}+\binom{n}{3}+\binom{n}{6}+...+\binom{n}{n}$
118024
Simplify the expression $\binom{n}{0}+\binom{n+1}{1}+\binom{n+2}{2}+\cdots +\binom{n+k}{k}$
70354
Find the sum of all the multiples of 3 or 5 below 1000
35342
Show that $ \sum_{n=2}^m \binom{n}{2} = \binom{m+1}{3}$
51008
Evaluating a sum involving binomial coefficient in denominator
57986
Sum of products of combinatorials
14399
Calculate $\sum_{k=1}^n (-1)^{k+1} \binom{n}{k}\frac{1}{k}$
439
Alternating binomial sum with intervals of two
126888
How can you show that $\binom {n}{7}=\sum_{k=7}^n \binom {k-1} {6}$?
34803
Evaluating even binomial coefficients
150355
Finding sum of binomial series
72639
Show that $\sum_{k=0}^n\binom{3n}{3k}=\frac{8^n+2(-1)^n}{3}$
108401
Sum of binomial coefficients $\sum_{k=0}^{n}(-1)^k\binom{n}{k}\binom{2n - 2k}{n - 1} = 0$
143927
Binomial coefficients that are powers of 2
148949
Find the value of $\sum_{k=1}^{n} k \binom {n} {k}$
142978
combinatorics: sum of product of integer compositions
99843
How to simplify $ \sum_{k=0}^{\infty} \binom{k + r - 1}{k} x^k$