Why was my question closed here? Probability every team successfully presents a solution
At a summer math program a contest is held for $n$ teams. Each team, composed of $n$ individuals, is given the same $n$ problems to work on. Suppose that on each team, there is one person who knows how to solve all $n$ problems, another who knows how to solve $n-1$ of the problems, and so on down to one member who only knows how to solve a single problem. One person is chosen from each team at random. These selected individuals are randomly ordered and asked one at a time to select a problem that has not already been taken. What is the probability that every team successfully presents a solution?
I had asked my professor and other graduate students in the department, and they all did not know how to do this problem. I know MO has had some debates recently (over the last year or two) on whether or not it is welcoming to graduate students. Clearly MO is not welcoming if this question was downvoted to oblivion, even when a tenured faculty member and fellow graduate students did not know how to solve it. MO wants to intimidate graduate students into thinking their questions are too trivial by deeming them offtopic.
For all the inanity and Red Guards posturing of math graduate students (and even faculty) on Twitter, this is nonetheless a real problem that they've highlighted about MO's unfriendliness.