\begin{table}%t3
\caption {\label{table:3}Numerical results for the weighted fits of the 18.6-yr nutation term plus the secular and constant terms for the LLR series.} % title of Table
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\begin{tabular}{c r r} % centered columns (4 columns)
\hline\hline % inserts double horizontal lines
Terms & $DX$ (mas) & $DY$ (mas) \\ % table heading
\hline % inserts single horizontal line
sin (18.6-yr) & $ 0.002\pm 0.221$  & $ -0.022\pm 0.206$ \\
cos (18.6-yr) & $ 0.009\pm 0.129$ & $-0.215\pm 0.123$ \\ 
secular term (mas/cy) & $5.769 \pm 3.246$ & $1.068 \pm 3.108$ \\
constant term & $0.270 \pm 0.134$ & $-0.174 \pm 0.125$ \\
\hline %inserts single line
\end{tabular}
\end{table}