Does anyone know how to reduce this sum of sums into something simpler in order to find a special value?
74149
Reducing an indicator function summation into a simpler form.
22657
How to find the sum of the infinite series?
124135
A general formula for $\sum (k-1)(k-2)(k-3)$?
104646
Question on simplification of $\sum_{n=1}^{\infty}\frac{2}{(2n+1)(2n+3)}$?
153409
Sum of $1+\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+\frac{1}{6}+\frac{1}{8}+\frac{1}{9}+\frac{1}{12}+\cdots$
47463
Converting sums of square-roots to nested square-roots
74120
Find the value of $\sum_{n=1}^{\infty} \frac{2}{n}-\frac{4}{2n+1}$
146305
Simplify sum of factorials with mathematical induction
50606
Find $\sum\limits_{k\, \text{ odd}} \frac{2(k^2-1)}{k^4+k^2+1}$
37650
Find $\sum_{m=0}^n\ (-1)^m m^n {n \choose m}$
102339
How to compute the sum of a series
74682
How should I solve combination addition like this?
116722
Simplifying $\big(\sum_{i=0}^n\binom{k}{i}\binom{M-k}{n-i}\frac{k-i}{M-n}\big)/{\binom{M}{n}}$
135218
Closed Form for Factorial Sum
102486
Simplifying $\sum_{i=1}^n{\lfloor \frac{n}{i} \rfloor}$?
31731
How to turn this into an equation and then sum the series?
63965
How can I compute the sum of $ {m\over\gcd(m,n)}$?