How to calculate $k^0+k^1+k^2 + k^3+...+ k^{n-1}$
2678
Values of $\sum_{n=0}^\infty x^n$ and $\sum_{n=0}^N x^n$
155496
sum of combinations $\binom n{0} + \binom n{3} + \binom n{6} +... +\binom n{3k}$
8806
Summation of binomial coefficients
74898
$1^n +2^n + \cdots +(p-1)^n \mod p =$?
99453
Sum of $k$-th powers
64581
How to find the sum $\sum\limits_{k=1}^n (k^2+k+1)k!$?
122534
Show that $\sum (-1)^{n+1}/n$ = $k$ can be expanded to a sum with $ 1 - 1/2 + 1/3 + 1/5 - 1/4 +1/7 + 1/9 - 1/6 + ....$ which is $3k/2$
36436
Proving $\sum_{k=1}^n k k!=(n+1)!-1$
94060
Sum of square binomial coefficients
124135
A general formula for $\sum (k-1)(k-2)(k-3)$?
96237
$1^2 + 2^2 + 3^2 + \cdots + (n-1)^2 \equiv 0$ mod n iff $n \equiv \pm 1$ mod 6
17390
Find $LK_1^2 + LK_2^2 + \dots + LK_{11}^2$.
118372
Combination proof for $n(n+1)2^{n-2}=\sum_{k=1}^{n}k^2\binom{n}{k}$
21000
Calculating $\sum_{k=1}^nk(k!)$ combinatorially
86900
Formula for the $1\cdot 2 + 2\cdot 3 + 3\cdot 4+\ldots + n\cdot (n+1)$ sum
87589
Evaluate $\binom{n}{0}+\binom{n}{2}+\binom{n}{4}+...+\binom{n}{2k}$
562
Formula for calculating $\sum_{n=0}^{m}nr^n$