current bounds on the number of colors: 0 -- 3 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 17:55:52 2012 Optimize a model with 6 rows, 6 columns and 12 nonzeros Presolve removed 6 rows and 6 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 - current bounds on the number of colors: 1 -- 3 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 17:55:52 2012 Optimize a model with 9 rows, 9 columns and 24 nonzeros Presolve removed 3 rows and 3 columns Presolve time: 0.00s Presolved: 6 rows, 6 columns, 18 nonzeros Variable types: 0 continuous, 6 integer (6 binary) Root relaxation: objective 0.000000e+00, 3 iterations, 0.00 seconds Nodes | Current Node | Objective Bounds | Work Expl Unexpl | Obj Depth IntInf | Incumbent BestBd Gap | It/Node Time 0 0 0.00000 0 3 - 0.00000 - - 0s 0 0 infeasible 0 - 0.10000 - - 0s Explored 0 nodes (5 simplex iterations) in 0.00 seconds Thread count was 1 (of 16 available processors) Model objective exceeds cutoff Best objective -, best bound 1.000000000000e+00, gap - optimal solution found: number of colors: 3