Any algebraic function that can be expanded as infinite series with unbounded positive integral coefficients?

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Cound one give examples of irrational algebraic function that can be expanded as infinite series with unbounded positive integral coefficients, like:

$$f(x)=\sum_0^{\infty}a_i x^i,\qquad a_i\in \mathbb{N} \cup \{0\}$$

I post the question for interest, since the first time it has not been clearly expressed, I have updated the question.

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$$\frac{1 - \sqrt{1 - 4x}}{2x} = \sum_{k=0}^\infty C_n x^n$$ where $C_n$ are the Catalan numbers.

There are many other examples in the OEIS.