current bounds on the number of colors: 0 -- 53 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 19:36:31 2012 Optimize a model with 4057 rows, 1532 columns and 13390 nonzeros Presolve time: 0.02s Presolved: 4057 rows, 1532 columns, 13390 nonzeros Variable types: 0 continuous, 1532 integer (1532 binary) Root relaxation: objective 0.000000e+00, 132 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 (222 simplex iterations) in 0.03 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 -- 26 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 19:36:31 2012 Optimize a model with 2055 rows, 843 columns and 6695 nonzeros Presolve time: 0.01s Presolved: 2055 rows, 843 columns, 6695 nonzeros Variable types: 0 continuous, 843 integer (843 binary) Root relaxation: objective 0.000000e+00, 112 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 (194 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 -- 13 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 19:36:31 2012 Optimize a model with 977 rows, 472 columns and 3090 nonzeros Presolve time: 0.00s Presolved: 977 rows, 472 columns, 3090 nonzeros Variable types: 0 continuous, 472 integer (472 binary) Root relaxation: objective 0.000000e+00, 111 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 (199 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 -- 6 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 19:36:31 2012 Optimize a model with 515 rows, 313 columns and 1545 nonzeros Presolve time: 0.00s Presolved: 515 rows, 313 columns, 1545 nonzeros Variable types: 0 continuous, 313 integer (313 binary) Root relaxation: objective 0.000000e+00, 123 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 87 - 0.00000 - - 0s 0 0 infeasible 0 - 0.10000 - - 0s Cutting planes: Gomory: 5 Clique: 24 MIR: 1 Zero half: 11 Explored 0 nodes (628 simplex iterations) in 0.02 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: 3 -- 6 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 19:36:31 2012 Optimize a model with 669 rows, 366 columns and 2060 nonzeros Presolve time: 0.00s Presolved: 669 rows, 366 columns, 2060 nonzeros Variable types: 0 continuous, 366 integer (366 binary) Root relaxation: objective 0.000000e+00, 117 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 (333 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: 4