current bounds on the number of colors: 0 -- 9 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 19:35:31 2012 Optimize a model with 21 rows, 39 columns and 72 nonzeros Presolve removed 4 rows and 16 columns Presolve time: 0.00s Presolved: 17 rows, 23 columns, 56 nonzeros Variable types: 0 continuous, 23 integer (23 binary) Root relaxation: objective 0.000000e+00, 8 iterations, 0.00 seconds Nodes | Current Node | Objective Bounds | Work Expl Unexpl | Obj Depth IntInf | Incumbent BestBd Gap | It/Node Time * 0 0 0 0.0000000 0.00000 0.0% - 0s Explored 0 nodes (8 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 Thu Dec 13 19:35:31 2012 Optimize a model with 15 rows, 21 columns and 36 nonzeros Presolve removed 11 rows and 16 columns Presolve time: 0.00s Presolved: 4 rows, 5 columns, 12 nonzeros Variable types: 0 continuous, 5 integer (5 binary) Root relaxation: objective 0.000000e+00, 2 iterations, 0.00 seconds Nodes | Current Node | Objective Bounds | Work Expl Unexpl | Obj Depth IntInf | Incumbent BestBd Gap | It/Node Time * 0 0 0 0.0000000 0.00000 0.0% - 0s Explored 0 nodes (2 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 Thu Dec 13 19:35:31 2012 Optimize a model with 12 rows, 12 columns and 18 nonzeros Presolve removed 12 rows and 12 columns Presolve time: 0.00s Explored 0 nodes (0 simplex iterations) in 0.00 seconds Thread count was 1 (of 16 available processors) Model objective exceeds cutoff Best objective -, best bound -, gap - optimal solution found: number of colors: 2