\documentclass{article}

\documentclass{article}
\usepackage{amsmath} % pkg required by EasyLatex
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\begin{document}

\begin{align*}x \mapsto y_1\ldots y_n
\\ \\ \\ \frac{1}{3}
\\ \\ \\ 1 + 1 &= 2
\\1 &\leq 3 - 1
\\&\leq 5
\end{align*}

\end{document}