%TABELLA SEQUENZA 2

\begin{table}
\begin{center}
\begin{tabular}{|c|c|c|c|}
\hline
\multicolumn{4}{|c|}{\textbf{Enumerating sequence: $\{2\}_{n\geq 2}$}}\\
\hline \hline

\emph{1st pattern}&\emph{2nd pattern}&\emph{3rd pattern}&\emph{4th
pattern}\\
\hline \hline

$\begin{array}{c}
  1-23 \\
\end{array}$

&

$\begin{array}{l}
  2-31\ \ or \\
  23-1 \\
\end{array}$

&

$\begin{array}{l}
  1-32\ \ or \\
  13-2 \\
\end{array}$

&

$\begin{array}{l}
  3-12\ \ or \\
  31-2 \\
\end{array}$

\\ \hline

$\begin{array}{c}
  1-23 \\
\end{array}$

&

$\begin{array}{l}
  2-13\ \ or \\
  21-3 \\
\end{array}$

&

$\begin{array}{l}
  1-32\ \ or \\
  13-2 \\
\end{array}$

&

$\begin{array}{l}
  3-12\ \ or \\
  31-2 \\
\end{array}$

\\ \hline

$\begin{array}{l}
  2-13\ \ or \\
  21-3 \\
\end{array}$

&

$\begin{array}{l}
  2-31\ \ or \\
  23-1 \\
\end{array}$

&

$\begin{array}{l}
  1-32\ \ or \\
  13-2 \\
\end{array}$

&

$\begin{array}{l}
  3-12\ \ or \\
  31-2 \\
\end{array}$

\\ \hline

$\begin{array}{c}
  12-3 \\
\end{array}$

&

$\begin{array}{l}
  2-13\ \ or \\
  21-3 \\
\end{array}$

&

$\begin{array}{l}
  2-31\ \ or \\
  23-1 \\
\end{array}$

&

$\begin{array}{c}
  32-1 \\
\end{array}$

\\ \hline

$\begin{array}{c}
  1-23 \\
\end{array}$

&

$\begin{array}{l}
  2-13\ \ or \\
  21-3 \\
\end{array}$

&

$\begin{array}{l}
  2-31\ \ or \\
  23-1 \\
\end{array}$

&

$\begin{array}{l}
  3-12\ \ or \\
  31-2 \\
\end{array}$

\\ \hline

$\begin{array}{c}
  1-23 \\
\end{array}$

&

$\begin{array}{l}
  2-13\ \ or \\
  21-3 \\
\end{array}$

&

$\begin{array}{l}
  2-31\ \ or \\
  23-1\\
\end{array}$

&

$\begin{array}{l}
  1-32\ \ or \\
  13-2 \\
\end{array}$

\\ \hline
\end{tabular}
\end{center}
\caption{permutations avoiding four patterns}\label{4mot_2}
\end{table}