\begin{tabular}{|l|l|l|l|c|c|}
\hline Proof obligations & \provername{Alt-Ergo 0.99.1} & \provername{Coq 8.7.1} \\ 
\hline
\explanation{G1} & \valid{0.00} & \noresult\\ 
\hline
\explanation{G2} & \unknown{0.00} & \noresult\\ 
\cline{2-3}
\quad\transformation{split\_goal\_right} & \multicolumn{2}{|c|}{}\\
\cline{2-3}
\quad\subgoal{G2.0}{1} & \unknown{0.00} & \unknown{0.29} \\ 
\cline{2-3}
\quad\subgoal{G2.1}{2} & \valid{0.00} & \noresult\\ 
\hline
\explanation{G3} & \valid{0.00} & \noresult\\ 
\hline \end{tabular}
