Time Complexity Guide

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\begin{document}
\begin{center}
\begin{tabular}{ | m{5em} | m{5cm}| }
  \hline
   $n \leq 10$ & $\mathcal{O}(n!)$\\
  \hline
   $n \leq 20$ & $\mathcal{O}(2^{n})$\\
  \hline
   $n \leq 50$ & $\mathcal{O}(n^{5})$\\
  \hline
   $n \leq 100$ & $\mathcal{O}(n^{4})$\\
  \hline
   $n \leq 500$ & $\mathcal{O}(n^{3})$\\
  \hline
   $n \leq 3000$ & $\mathcal{O}(n^{2}\cdot \log{n})$\\
  \hline
   $n \leq 5000$ & $\mathcal{O}(n^{2})$\\
  \hline
   $n \leq 10^{5}$ & $\mathcal{O}(n\cdot \log{n}) \sim \mathcal{O}(n\cdot \sqrt{n})$\\
  \hline
   $n \leq 10^{6}$ & $\mathcal{O}(n\cdot \log{n}) \sim \mathcal{O}(n)$\\
  \hline
   $n \leq 10^{12}$ & $\mathcal{O}(\sqrt{n})$\\
  \hline
   $n \leq 10^{18}$ & $\mathcal{O}(\log{n})$\\
  \hline
\end{tabular}
\end{center}
\end{document}