\documentclass{article}
\usepackage{latexml}
\usepackage{amsmath}
\begin{document}
% Parse rule tree: 
% 1 AnythingAny 
% 2  METARELOP Formula  
% 3  METARELOP ( Expression extendFormula )  
% 4  METARELOP (( SignedTerm moreTerms addExpressionModifier ) ( relop Expression moreRHS ))  
% 5  METARELOP ((( Term ) moreTerms addExpressionModifier ) (( RELOP addOpDecoration ) ( SignedTerm moreTerms addExpressionModifier ) moreRHS ))  
% 6  METARELOP (((( Factor moreFactors )) moreTerms addExpressionModifier ) (( RELOP addOpDecoration ) (( Term ) moreTerms addExpressionModifier ) moreRHS ))  
% 7  METARELOP ((((( preScripted doubtArgs ) moreFactors )) moreTerms addExpressionModifier ) (( RELOP addOpDecoration ) ((( Factor moreFactors )) moreTerms addExpressionModifier ) moreRHS ))  
% 8  METARELOP (((((( <matchrule:$arg[0]> addScripts ) doubtArgs ) moreFactors )) moreTerms addExpressionModifier ) (( RELOP addOpDecoration ) (((( NUMBER addScripts ) moreFactors )) moreTerms addExpressionModifier ) moreRHS ))  
% lex  METARELOP (((((( <matchrule:$arg[0]> ))))) (( RELOP ) (((( NUMBER )))))) 
$ \vdash x = 0$ 
\end{document}