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.


Homework Equations





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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Show us your work so we can help you.

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).