During the execution of a test plan, a test manager may decide to drop a test case if its result can be inferred from already executed test cases. We show that it is possible to automatically generate a test plan to exploit the potential to justifiably drop a test case and thus reduce the number of test cases. Our approach uses Boolean formulas to model the mutual dependencies between test results. The algorithm to generate a test plan comes with the formal guarantee of optimality with regards to the inference of the result of a test case from already executed test cases.