A few minutes ago I put a comment on a question by https://math.stackexchange.com/users/50707/kalima asking where he found his problem. The problem was something along the lines of Diophantine $4 a^2 (b^2 + c^2) = 5 b^2 c^2$ in some arrangement of symbols. Within a couple of minutes of my request, the question was self-deleted. If I had taken the trouble to write down the question number I could see the thing just by clicking on any question and replacing the number.
Part 2, on MO I can click on a sequence of things and view all deletions back to the beginning of the site. I did this once. There was someone trying to use MO to resolve a question for him. He would post a version of the question for a short time, delete, repost. Eventually I collected some 55 occurrences of this as screen capture jpegs. The later MO Meta post on this is http://tea.mathoverflow.net/discussion/1187/extending-from-a-plane-in-r3-again-and-again-and-again
So, you see, I get suspicious when someone is pretty demanding about the nature of the answers but then self-deletes when asked for the source of the problem. Lately I have been asking nearly everyone for the sources of their questions; if a question is legitimate as I personally view the term, this should elicit a source and some context. If, as seems to happen a fair amount, the source is an IMO from 1977, at least I know that someone responsible believed the problem statement to be correct at that time.
So, to repeat, at 15K, do I have some way to view a list of items deleted (recently?).
EDDDITTT: Old John pointed out that the user had been discussing this on Chat, which I have never figured out. However, I was just able to search, and found https://math.stackexchange.com/questions/249317/generating-valid-integer-solutions-to-4a2b2-c2-5b2c2 which is a start.
EEEEDIIIIIT: the chat transcript for the relevant two hours is http://chat.stackexchange.com/transcript/36/2012/12/2/18-20 where the first item in those two hours is the question, while the final one says something about giving up. In the next two hour slot Old John asks the reason for the deletion. Life goes on.
EDDD333DDITTTT: note that this is the same obliging fellow as Generating Pythagorean triples for $a^2+b^2=5c^2$? My request for the source of these questions was unsuccessful and I have deleted it.