current bounds on the number of colors: 0 -- 20 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 17:56:00 2012 Optimize a model with 1020 rows, 300 columns and 3200 nonzeros Presolve time: 0.00s Presolved: 1020 rows, 300 columns, 3200 nonzeros Variable types: 0 continuous, 300 integer (300 binary) Root relaxation: objective 0.000000e+00, 48 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 (92 simplex iterations) in 0.01 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 -- 10 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 17:56:00 2012 Optimize a model with 520 rows, 200 columns and 1600 nonzeros Presolve time: 0.00s Presolved: 520 rows, 200 columns, 1600 nonzeros Variable types: 0 continuous, 200 integer (200 binary) Root relaxation: objective 0.000000e+00, 40 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 26 - 0.00000 - - 0s 0 0 0.00000 0 33 - 0.00000 - - 0s 0 0 0.00000 0 36 - 0.00000 - - 0s 0 0 0.00000 0 53 - 0.00000 - - 0s 0 0 infeasible 0 - 0.10000 - - 0s Cutting planes: Clique: 5 Zero half: 45 Explored 0 nodes (928 simplex iterations) in 0.04 seconds Thread count was 1 (of 16 available processors) Model objective exceeds cutoff Best objective -, best bound 1.000000000000e+00, gap - current bounds on the number of colors: 5 -- 10 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 17:56:00 2012 Optimize a model with 720 rows, 240 columns and 2240 nonzeros Presolve time: 0.00s Presolved: 720 rows, 240 columns, 2240 nonzeros Variable types: 0 continuous, 240 integer (240 binary) Root relaxation: objective 0.000000e+00, 46 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 (200 simplex iterations) in 0.01 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: 5 -- 7 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 17:56:00 2012 Optimize a model with 620 rows, 220 columns and 1920 nonzeros Presolve time: 0.00s Presolved: 620 rows, 220 columns, 1920 nonzeros Variable types: 0 continuous, 220 integer (220 binary) Root relaxation: objective 0.000000e+00, 41 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 20 - 0.00000 - - 0s H 0 0 0.0000000 0.00000 0.0% - 0s Explored 0 nodes (258 simplex iterations) in 0.01 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: 6