\documentclass[12pt]{amsart}

\begin{document}

$$ \int\limits_0^1 x\,dx = \frac{x^2}{2} \biggl|_{x=0}^{x=1} $$ 

$$ \left. \int\limits_0^1 x\,dx = \frac{x^2}{2} \right|_{x=0}^{x=1} $$ 

$$ \left. \int_0^1 x\,dx = \frac{x^2}{2} \right|_{x=0}^{x=1} $$ 

$$ \sum' $$

$$ {\sum}' $$

$$ {\sum_{k=1}^n}' $$

$$ \mathop{{\sum}'}_{k=1}^n $$

$$ {}_1^2 {\mathop{A}^3_6}\,{}^4_5 $$

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2&0&1&0&\,&1&5& \\
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1&5& & & &1&3&4\\
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 &5&1\\
 &4&5\\
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 & &6&0\\
 & &6&0\\
\cline{3-4}
 & & &0\\
\end{array}
$$

\end{document}
