$$x + \frac1x + \cfrac1{x + \frac1x} + \cfrac1{x + \frac1x + \cfrac1{x + \frac1x}} +\cfrac1{x + \frac1x + \cfrac1{x + \frac1x} + \cfrac1{x + \frac1x + \cfrac1{x + \frac1x}} } + \cdots $$
How can this series be simplified? Consider me as a high school graduate.
By setting $a_1=x$ and $a_N = \frac{1}{a_1+a_2+\ldots+a_{N-1}}$ we may easily see that there are quite a lot convergence issues. If $a_1+a_2+a_N\to L\neq 0$, then $a_N\to \frac{1}{L}$, contradicting the convergence of the series. On the other hand also $a_1+a_2+\ldots+a_N\to 0$ leads to a contradiction, hence your series cannot be convergent.