\begin{table}%t4
\caption{\label{table:freq_A}HD~181906 frequencies (in $\mu$Hz) for scenario~A.}
%\centering
\small
\begin{tabular}{crrr}
\hline\hline
&  & \multicolumn{1}{c}{Scenario A}  & \\
\multicolumn{1}{c}{\# } & \multicolumn{1}{c}{$l=0$} & \multicolumn{1}{c}{$l=1$} & \multicolumn{1}{c}{$l=2$} \\ 
\hline  
1  &  1524.80~$\pm$~0.86  &  1565.61~$\pm$~0.38  &  1521.98~$\pm$~0.42 \\
2  &  1604.89~$\pm$~0.25  &  1645.98~$\pm$~0.41  &  1596.46~$\pm$~0.51 \\ 
3  &  1684.62~$\pm$~0.40  &  1734.98~$\pm$~0.53  &  1687.32~$\pm$~0.51 \\
4  &  1773.14~$\pm$~0.27  &  1814.29~$\pm$~0.31  &  1772.43~$\pm$~0.39 \\
5  &  1862.25~$\pm$~0.53  &  1898.77~$\pm$~0.27  &  1861.74~$\pm$~0.39 \\
6  &  1947.42~$\pm$~0.30  &  1988.32~$\pm$~0.37  &  1946.26~$\pm$~0.28 \\  
7  &  2035.88~$\pm$~0.62  &  2076.45~$\pm$~0.51  &  2036.30~$\pm$~0.95 \\
\hline
\end{tabular}
\end{table}