What Are the Properties of the Sequence (Xn)?

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Homework Statement


let (Xn) be a sequence in R given by X1=1 and Xn+1=1/(3+Xn) for n>=2. prove Xn converges and find the limit.


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The Attempt at a Solution


well i think using the monotone convergence theorem would help but i would have to prove that the sequence is bounded and monotone. But I have not been able to prove it is monotone yet.
 
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Sometimes it helps to generate the first few terms of a sequence.
 
X2=1/4, X3=4/13, X4=13/43, X5=43/142... the sequence kinda flips up and down. it will go down, up, down,... it does not seem monotone...
 
How is xn+2 related to xn ?

Then look at the subsequences, (x2n) and (x2n+1).
 
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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