\begin{table}%t4
\caption{\label{tab:useful}Color \irmag\ characterizing the spectral energy distribution
of main-sequence stars of luminosity class V (see text).}
\small%\centering
\par
\begin{tabular}{lcllcllc}
 \hline  \hline \noalign{\smallskip} 
{\it SpT} & \irmag & & {\it SpT} & \irmag  & & {\it SpT} & \irmag\\
\noalign{\smallskip}\hline\noalign{\smallskip} 
A0  &  0.00 & & M0  &  1.97 & & M6  &  3.34 \\
F0  &  0.42 & & M1  &  2.10 & & M7  &  3.77 \\
G0  &  0.79 & & M2  &  2.23 & & M8  &  4.38 \\
K0  &  1.20 & & M3  &  2.39 &  & M9  &  5.00 \\	  
K3  &  1.42 & & M4  &  2.61 &  & L0  &  \hspace{1mm}5.46:\\
K7  &  1.88 & & M5  &  2.94 &  & L1  &  \hspace{1mm}5.65:\\
 \hline 
\end{tabular}
\end{table}