%% 
%%  Example 04-01-24 
%%  Copyright (C) 2016 Herbert Voss
%% 
%% ==== 
% Show page(s) 1
%% 
%% 
\documentclass[]{screxa}
\pagestyle{empty}
\setlength\textwidth{158.31393pt}
\setlength\parindent{0pt}
%StartShownPreambleCommands
\usepackage{mathtools}
%StopShownPreambleCommands
\begin{document}
\begin{align}
 x &=
  \begin{lgathered}[t]
    a + b + c \\
    d + e +
      \!\begin{gathered}[t]
        f + g + h \\
        i + j + k
      \end{gathered}
  \end{lgathered}
\end{align}
\end{document}
