The Mathematics Department of Moscow State University, the most prestigious mathematics school in Russia, was at that time actively trying to keep Jewish students (and other \undesirables") from enrolling in the department.One of the methods they used for doing this was to give the unwanted students a different set of problems on their oral exam. I was told that these problems were carefully designed to have elementary solutions (so that the Department could
avoid scandals) that were nearly impossible to find. Any student who failed to answer could easily be rejected, so this system was an eective method of controlling admissions.
It was arbitrary.