On Lion’s counter example for Gotlieb’s method for the construction of school timetables

The timetable problem is an essentially discrete problem. Although the discrete problem may have no feasible solution, there may exist a solution to the equivalent continuous problem. An example, is given, for which the nondiscrete solution can be interpreted as a set of timetables, differing from week to week, which together satisfy the long-term requirements of the timetable problem.

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