\documentclass{article}
\usepackage{mathtools}
\begin{document}
\begin{align}
\tilde{C}=\left[\begin{matrix}
c_{i0}&c_{i1}&c_{2}&c_{i3}&\cdots &c_{i7}\\
1/3c_{i1}&c_{i0}&&&\cdots &\\
1/5c_{i2}&&&&\cdots &\\
1/7c_{i3}&&&&\cdots &\\
\vdots &\vdots & \vdots &\vdots &\cdots &\vdots\\
1/15c_{i7}&&&&\cdots &\\
\end{matrix} \right].
\end{align}     
\end{document}