What Is the Exact Value of the Infinite Series Sum of n^-n?

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Homework Statement


http://latex.codecogs.com/examples/00a93bb6c6c645f9802b88f4c1c986fc.gif
Let's call this L.
Find the exact value of L.

Homework Equations


http://latex.codecogs.com/examples/6835d744da9ce19b352158cd01b91e91.gif
1+1/2=1,5

The Attempt at a Solution


  • L>0.
  • 1,5>L
  • The function is always growing
Therefore there must be an definite answer in ]1,5 ; 0[
Wolfram gives 1,291286...Spam of possible methods:
-Trying to find the value relating it to integration. Impossible. The integral is not defined.
-Try to find an adequate Taylor Expansion. Can't find a function that fits AND I don't know any pretty method to relation expansions to functions.
-Try to find a relatable sum such as that of the differences or quocients of the next term. Couldn't do much with it.
-Use n^-n=e^ln(n^-n)=e^(-n*ln n). Can't do much with it.
-Turn into a product problem n^-n=ln(e^(n^-n)). Can't do much with it.
-Use a general formula for the sum of a^(k) to infinity. Haven't tried but it doesn't seem to simplify.Main question:
Is it representable using already known constants?
 
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There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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