\input{umtest-preamble} \usepackage{unicode-math} \setmathfont{Cambria Math} \begin{document} \[ \left\{ \left\{ \left\{ \left\{ \left\{ \left\{ x^2 \right\}^2 \right\}^2 \right\}^2 \right\}^2 \right\}^2 \right\} \] \end{document}