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	The sum of all reversed square numbers in one row:	$\lim_{n \to \infty}\sum_{k=1}^n \frac{1}{k^2}=\frac{\pi^2}{6}$
	
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	Presented as an enumerated document formula:
	\begin{equation}
		\lim_{n \to \infty} \sum_{k=1}^n \frac{1}{k^2}= \frac{\pi^2}{6}
		\label{eq:sum-rev-sq}
	\end{equation}
	The sum of all reversed square numbers: Formula \eqref{eq:sum-rev-sq}


	\vskip 8em		% alernate way to 'enforce' some vertical spacing


	\begin{equation}
		\left( \frac{\partial}{\partial t} + \sum_{j=1}^3 \left( u_j\frac{\partial}{\partial x_j} - \nu\frac{\partial^2}{\partial x_j\partial x_j} \right) \right) u_i
			= -\frac{\partial w}{\partial x_i} + g_i
		\label{eq:partial-alot}
	\end{equation}
	Using \textbackslash partial many times in formula \eqref{eq:partial-alot}


	
\end{document}	







