The answer is yes indeed. It is a special case of $\DeclareMathOperator{\brn}{brn}\brn$ function. $$ R=\frac{x^B-1}{x^N}=f_{B,N}(x) $$ $$ x=\operatorname{arc}f_{B,N}(R)=\brn_{B,N}(R) $$ $$ \brn_{B,N}(R)=\sum_{g=0}^\infty\left(\frac{R^g}{B^gg!}\prod_{r=1}^{g-1}(-Br+1+Ng)\right) $$ radius of convergence $$ \left|\frac{N^N(B-N)^{B-N}R^B}{B^B}\right|<1 $$ where $B, N, R \in C$.<br> The function $\brn$ is named after the mathematician [Erland Samuel Bring](https://en.wikipedia.org/wiki/Erland_Samuel_Bring). [Here there is an article][1] about [ultraexponentiation][2] and ultraroot, while [here there is a calculator][3] with $\brn$ button. [1]: http://glax-plato.ru/exam/Math/brn.pdf [2]: https://www.cyberforum.ru/blog_attachment.php?attachmentid=8110&d=1687342320 [3]: http://glax-plato.ru/