Evaluate $\sum_{k=1}^\infty \frac{k^2}{(k-1)!}$.
17713
What's the value of $\sum\limits_{k=1}^{\infty}\frac{k^2}{k!}$?
137155
Sum $ \sum\limits_{k=1}^{\infty} \frac{k^2}{2^k}$
151477
computing the series $\sum_{n=1}^\infty \frac{1}{n^2 2^n}$
64581
How to find the sum $\sum\limits_{k=1}^n (k^2+k+1)k!$?
125148
Summation of series $\sum_{k=0}^\infty 2^k/\binom{2k+1}{k}$
156720
Evaluate $\sum_ {n=1}^{\infty} \cot^{-1}(2n^2)$
81589
Find the sum of $\sum_{k=0}^{\infty} 1/[(r+2k+2)(s+2k+2)]$
99420
Compute $\sum_{n=1}^\infty \frac{1}{(n+1)\sqrt[]{n}+n\sqrt[]{n+1}}$
56961
Evaluate the limit of $\sum_{n=1}^{\infty}\frac{n^2}{n!}$
30518
Formula for $\sum_{k=1}^n \frac{1}{k(k+1)(k+2)}$?
69978
Evaluating $\int_1^\infty \frac{1}{x(x^2+1)}\ dx$
138313
How to sum $\sum_{n=1}^{\infty} \frac{1}{n^2 + a^2}$?
72502
Evaluate $\sum_{n=1}^\infty nx^{n-1}$
93690
How to obtain the sum of the following series? $\sum_{n=1}^\infty{\frac{n^2}{2^n}}$
155005
How to show $\sum_{k=n}^\infty{\frac{1}{k!}} \leq \frac{2}{n!}$
124229
Simplify $\sum_{k=0}^{\infty} x^ky^{\frac{k(k+1)}{2}}$
107789
Sum of $\sum \limits_{n=0}^{\infty} \frac{1}{(kn)!}$