%% 
%%  An UIT Edition example
%% 
%%  Example 04-04-3 on page 37.
%% 
%%  Copyright (C) 2010 Herbert Voss
%% 
%%  It may be distributed and/or modified under the conditions
%%  of the LaTeX Project Public License, either version 1.3
%%  of this license or (at your option) any later version.
%% 
%%  See http://www.latex-project.org/lppl.txt for details.
%% 
%% 
%% ==== 
% Show page(s) 1
%% 
\documentclass[]{exaarticle}
\pagestyle{empty}
\setlength\textwidth{177.70511pt}
\AtBeginDocument{\setlength\parindent{0pt}}
\setcounter{equation}{6}
\renewcommand\theequation{4.\arabic{equation}}
\StartShownPreambleCommands

\StopShownPreambleCommands
\begin{document}
\begin{equation}
\fboxsep=0pt\fboxrule=0.1pt
\fbox{$\sum_{{1\le i\le \sqrt{p^{-3}}\atop{
  {1\le j\le q\atop 1\le k\le r}}}}$}
\fbox{$a_{ij}b_{jk}c_{ki}$}
\end{equation}
\end{document}