%% 
%%  Example 01-16-1 
%%  Copyright (C) 2017 Herbert Voss
%% 
%% ==== 
% Show page(s) 1
%% 
%% 
\documentclass[]{screxa}
\pagestyle{empty}
\setlength\textwidth{110.31393pt}
\usepackage[T1]{fontenc}
\usepackage{kpfonts}
%StartShownPreambleCommands
\makeatletter
\newcommand\foo{\mathop{\operator@font foo}\nolimits}
\makeatother
%StopShownPreambleCommands
\begin{document}
\[ \foo_1^2 = x^2 \]
\end{document}
