Nonlinear difference equation

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Maybe this is a trivial question, but how to find the general solution to the following first order difference equation?

$$ y_{t+1}=a+\frac{b}{y_{t}} $$

Also, could someone recommend a reference textbook on difference (and possibly differential) equations? I would need a quite comprehensive text, at an intermediate level.

Thank you.

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I would write $y_t = \frac{p_t}{q_t}$, so the general step becomes

$$ \frac{p}{q} \rightsquigarrow a+\frac{bq}{p} = \frac{ap+bq}{p}$$

and the recurrence splits into two coupled linear ones:

$$ p_{t+1} = ap_t + bq_t $$ $$ q_{t+1} = p_t $$

Substituting the second of these into the first we get

$$ p_{t+1} = ap_t + bp_{t-1} $$

which can then be solved by standard methods.