\documentclass{article}
% NOTE These formula are EXPECTED to not parse!
% We're testing the fallback "Kludge" parser!
\usepackage{latexml}
\lxDeclare[role=ERROR]{$a$}%
\usepackage{amsfonts}
\begin{document}
\[ a + (b^{1^{2^3}}  +  (c^{2^3}  + (d^3  +  \]

\[ a +  b^1) +  c^{1^2}) + d^{1^{2^3}})  \]

\[ (a  + E)^3 \]

\[ a + (b + (c+d)^2+e)^3 + (f + (g+h)^2+i)^3
\]

\[ a +
 \mathbb P(\eta(x) \to 1) = \sum_{N=0}^\infty \sum_{j=0}^N \mathbb P(N_x=N \mathrm{ and } \frac{j-1}N<T_x\leq\frac{j}N) \bar C(y^\circ(x), T_x)
\]

\end{document}
