"Build string that eval()s to largest number given digits 1,2,3 and ops +, -, /, *"
Shit, I got this question on a programming interview a decade ago and bombed. Here a mathematician spends 30 minutes just going over the infotainment parts of the problem.
If I had to do this again, I would do montecarlo, the tool of choice of people who code better than they math.