current bounds on the number of colors: 0 -- 19 Gurobi 5.0.1 (linux64) logging started Sat Dec 15 16:12:48 2012 Optimize a model with 19 rows, 171 columns and 171 nonzeros Presolve removed 19 rows and 171 columns Presolve time: 0.00s Explored 0 nodes (0 simplex iterations) in 0.00 seconds Thread count was 1 (of 16 available processors) Optimal solution found (tolerance 1.00e-04) Best objective 0.000000000000e+00, best bound 0.000000000000e+00, gap 0.0% current bounds on the number of colors: 0 -- 9 Gurobi 5.0.1 (linux64) logging started Sat Dec 15 16:12:48 2012 Optimize a model with 19 rows, 76 columns and 76 nonzeros Presolve removed 19 rows and 76 columns Presolve time: 0.00s Explored 0 nodes (0 simplex iterations) in 0.00 seconds Thread count was 1 (of 16 available processors) Optimal solution found (tolerance 1.00e-04) Best objective 0.000000000000e+00, best bound 0.000000000000e+00, gap 0.0% current bounds on the number of colors: 0 -- 4 Gurobi 5.0.1 (linux64) logging started Sat Dec 15 16:12:48 2012 Optimize a model with 19 rows, 38 columns and 38 nonzeros Presolve removed 19 rows and 38 columns Presolve time: 0.00s Explored 0 nodes (0 simplex iterations) in 0.00 seconds Thread count was 1 (of 16 available processors) Optimal solution found (tolerance 1.00e-04) Best objective 0.000000000000e+00, best bound 0.000000000000e+00, gap 0.0% current bounds on the number of colors: 0 -- 2 Gurobi 5.0.1 (linux64) logging started Sat Dec 15 16:12:48 2012 Optimize a model with 19 rows, 19 columns and 19 nonzeros Presolve removed 19 rows and 19 columns Presolve time: 0.00s Explored 0 nodes (0 simplex iterations) in 0.00 seconds Thread count was 1 (of 16 available processors) Optimal solution found (tolerance 1.00e-04) Best objective 0.000000000000e+00, best bound 0.000000000000e+00, gap 0.0% optimal solution found: number of colors: 1