## 6 Observability of the graph
### Constrained Nonlinear Programming Model
\begin{table}
\begin{tabular}{l l l} \hline  & & [2-1, 2-4, 2-5, 2-6 \\  & & [4-2, 4-3, 4-6, 4-12 \\  & & [6-2, 6-7, 6-8, 6-10 \\  & & [9-6, 9-10, 9-11 \\
4 & 10 & 2, 4, 6, 9, 10, 12, 15, 19, 25, 27 \\  & & [10-6, 10-17, 10-21, 10-22 \\  & & [12-13, 12-14, 12-15, 12-16 \\  & & [15-12, 15-14, 15-18, 15-23 \\  & & [19-18, 19-20 \\  & & [25-24, 25-26, 25-27 \\  & & [27-25, 27-28, 27-29, 27-30] \\ \hline  & & SCIP Spatial Branch-and-Bound Algorithm \\ \hline  & & & [3-1, 3-4 \\  & & [5-2, 5-7 \\  & & [6-4, 6-7, 6-8 \\  & & [9-6, 9-10, 9-11 \\
3 & 10 & 3, 5, 6, 9, 10, 12, 15, 19, 25, 27 \\  & & [12-13, 12-15, 12-16 \\  & & [15-12, 15-14, 15-23 \\  & & [19-18, 19-20 \\  & & [25-24, 25-26, 25-57 \\  & & [27-28, 27-29, 27-30] \\ \hline  & & [3-1, 3-4 \\  & & [5-2, 5-7 \\  & & [6-2, 6-4, 6-7, 6-8 \\  & & [9-6, 9-10, 9-11 \\
4 & 10 & 3, 5, 6, 9, 10, 12, 15, 18, 25, 27 \\  & & [10-17, 10-20, 10-21, 10-22 \\  & & [12-13, 12-14, 12-15, 12-16 \\  & & [15-12, 15-14, 15-18, 15-23 \\  & & [18-15, 18-19 \\  & & [25-24, 25-26, 25-27 \\  & & [27-25, 27-28, 27-29, 27-30] \\ \hline  & & Gurobi: Branch-and-Bound Algorithm \\ \hline  & & [2-1, 2-5, 2-6 \\  & & [3-1, 3-4 \\  & & [6-7, 6-8, 6-28 \\  & & [9-6, 9-10, 9-11 \\
3 & 10 & 2, 3, 6, 9, 10, 12, 18, 24, 26, 27 \\  & & [12-13, 12-14, 12-16 \\  & & [18-15, 18-19 \\  & & [24-22, 24-23, 24-25 \\  & & [26-25 \\  & & [27-25, 27-29, 27-30] \\ \hline  & & [1-2, 1-3 \\  & & [2-1, 2-4, 2-5, 2-6 \\  & & [6-7, 6-8, 6-9, 6-10 \\  & & [9-6, 9-10, 9-11 \\  & & [19-18, 19-20 \\
4 & 10 & 1, 2, 6, 9, 10, 12, 18, 24, 25, 27 \\  & & [27-25, 27-28, 27-29, 27-30] \\ \hline \end{tabular}
\end{table} 
Table 10: Cont. \begin{table}
\begin{tabular}{c c c} \hline \hline \multicolumn{2}{c}{MOSEK: Branch-and-Bound Algorithm} \\ \hline  & & [1-2, 1-3 \\  & & 2-1, 2-5, 2-6 \\  & & 6-4, 6-7, 6-8 \\  & & 9-6, 9-10, 9-11 \\
3 & 10 & 1, 2, 6, 9, 10, 12, 15, 20, 25, 27 & 10-17, 10-21, 10-22 \\  & & 12-13, 12-14, 12-16 \\  & & 15-12, 15-18, 15-23 \\  & & 20-10, 20-19 \\  & & 25-24, 25-26, 25-27 \\  & & 27-28, 27-29, 27-30 \\ \hline  & & \{1-2, 1-3 \\  & & 5-2, 5-7 \\  & & 6-8, 6-28 \\  & & 9-6, 9-10, 9-11 \\
4 & 10 & 1, 5, 6, 9, 10, 12, 18, 23, 25, 27 \\  & & 12-4, 12-13, 12-14, 12-16 \\  & & 18-15, 18-19 \\  & & 23-15, 23-24 \\  & & 25-24, 25-26, 25-27 \\  & & 27-25, 27-28, 27-29, 27-30\} \\ \hline \hline \end{tabular}
\end{table} 
Table 10: _Cont._

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