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Integral: $\int a$. Letters: $x$, $y$. Subscript: $P_{x}$, $P_{y}$. Fractions: $\frac{3}{4}$,
$\frac{\frac{1}{4}+2}{8+\frac{5}{7}}$, $\frac{\frac{\frac{1132}{3}}{2}}{\frac{\frac{1133}{3}}{2}}$.
Braces:$\overbrace{142}\underbrace{857}$.
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