Mister Exam

Other calculators

n^n/factorial(n+3)
Sum of series/ n^n/factorial(n+3)

Sum of series n^n/factorial(n+3)


∑
=

The solution

You have entered [src] 
  oo          
____          
\   `         
 \        n   
  \      n    
  /   --------
 /    (n + 3)!
/___,         
n = 1
$$\sum_{n=1}^{\infty} \frac{n^{n}}{\left(n + 3\right)!}$$ 
Sum(n^n/factorial(n + 3), (n, 1, oo))
The radius of convergence of the power series
Given number:
$$\frac{n^{n}}{\left(n + 3\right)!}$$
It is a series of species
$$a_{n} \left(c x - x_{0}\right)^{d n}$$
- power series.
The radius of convergence of a power series can be calculated by the formula:
$$R^{d} = \frac{x_{0} + \lim_{n \to \infty} \left|{\frac{a_{n}}{a_{n + 1}}}\right|}{c}$$
In this case
$$a_{n} = \frac{n^{n}}{\left(n + 3\right)!}$$
and
$$x_{0} = 0$$
,
$$d = 0$$
,
$$c = 1$$
then
$$1 = \lim_{n \to \infty}\left(n^{n} \left(n + 1\right)^{- n - 1} \left|{\frac{\left(n + 4\right)!}{\left(n + 3\right)!}}\right|\right)$$
Let's take the limit
we find
False

False

False
The rate of convergence of the power series
The graph
Sum of series n^n/factorial(n+3)

    Examples of finding the sum of a series

    © Mister Exam – Calculator