A digression, but this reminds me of the true story where a student solves such a problem!
One day in 1939, George Bernard Dantzig, a doctoral candidate at the University of California, Berkeley, arrived late for a graduate-level statistics class and found two problems written on the board. Not knowing they were examples of “unsolved” statistics problems, he mistook them for part of a homework assignment, jotted them down, and solved them.
Said Dantzig “A few days later I apologized to Neyman for taking so long to do the homework — the problems seemed to be a little harder than usual.”
The Legend of the 'Unsolvable Math Problem' | Snopes.com