Determine Limit of Factorial Sequence a_n

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    Factorial Limit
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Homework Statement


Determine the divergence or the convergence of the sequence. If it converges find its limit.

a_{n} = (\frac{(n)!}{2n!+1})


The Attempt at a Solution



All I know about factorials is for example 4! = 1*2*3*4. So as far as limits go I'm clueless. please help!
 
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I like to think of limits this way. First intuatively say why it should converge or diverge, then apply the intuation in a rigorous way. In this case both top and bottom are about the same thing so you would expect it to converge. How to say this in a formal manner? Use an inequality that will enable you to cancel the factorials and use the theorem that says if 0 \leq a_n \leq b_n for each n, then if b_n converges, so does a_n.
 
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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