*** QuickLaTeX cannot compile formula:
\begin{tikzpicture}
\foreach \z in {1,2,...,5}
\foreach \y in {1,2,...,5}
\foreach \x in {1,2,...,5}
\shade[ball color=black](\x,\z,\y) circle(0.5cm);
\end{tikzpicture}

*** Error message:
Environment tikzpicture undefined.
leading text: \begin{tikzpicture}