current bounds on the number of colors: 0 -- 54 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 19:36:37 2012 Optimize a model with 4698 rows, 1630 columns and 15390 nonzeros Presolve time: 0.02s Presolved: 4698 rows, 1630 columns, 15390 nonzeros Variable types: 0 continuous, 1630 integer (1630 binary) Root relaxation: objective 0.000000e+00, 142 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 (260 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 -- 27 Gurobi 5.0.1 (linux64) logging started Thu Dec 13 19:36:37 2012 Optimize a model with 2290 rows, 874 columns and 7410 nonzeros Presolve time: 0.01s Presolved: 2290 rows, 874 columns, 7410 nonzeros Variable types: 0 continuous, 874 integer (874 binary) Root relaxation: objective 0.000000e+00, 113 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 (191 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 19:36:37 2012 Optimize a model with 1086 rows, 496 columns and 3420 nonzeros Presolve time: 0.00s Presolved: 1086 rows, 496 columns, 3420 nonzeros Variable types: 0 continuous, 496 integer (496 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 (290 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 19:36:37 2012 Optimize a model with 570 rows, 334 columns and 1710 nonzeros Presolve time: 0.00s Presolved: 570 rows, 334 columns, 1710 nonzeros Variable types: 0 continuous, 334 integer (334 binary) Root relaxation: objective 0.000000e+00, 130 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 0 106 - 0.00000 - - 0s 0 0 0.00000 0 104 - 0.00000 - - 0s 0 0 0.00000 0 126 - 0.00000 - - 0s 0 0 0.00000 0 149 - 0.00000 - - 0s 0 0 infeasible 0 - 0.10000 - - 0s Cutting planes: Gomory: 2 Zero half: 154 Explored 0 nodes (1649 simplex iterations) in 0.09 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 19:36:37 2012 Optimize a model with 742 rows, 388 columns and 2280 nonzeros Presolve time: 0.00s Presolved: 742 rows, 388 columns, 2280 nonzeros Variable types: 0 continuous, 388 integer (388 binary) Root relaxation: objective 0.000000e+00, 114 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 (646 simplex iterations) in 0.02 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