# Question mysteriously deleted

I answered a question earlier today. It asked something like for an element $g$ of a free group, does there exist a finite-index subgroup of the free group such that g is a basis element of the subgroup. The author seems to have deleted the question. I can't seem to find it in my history (but I switch computers frequently and don't remember which one I was using).

Can a moderator locate the deleted question? One concern of mine is that it would have been a pretty good homework question for an course in geometric group theory. That's the only real reason I can imagine it being deleted (since it had multiple upvotes when I answered it).

• Do you mean this one?: mathoverflow.net/questions/252184/… – Stefan Kohl Oct 14 '16 at 21:42
• Yes, that's the one. It's a fine question, and I can't think of any reason it would be deleted. – Andy Putman Oct 14 '16 at 21:48
• I flagged it, and also voted to undelete. – Stefan Kohl Oct 14 '16 at 21:54
• @stefan kohl: Thanks! – Andy Putman Oct 14 '16 at 22:04
• It's now undeleted. – Todd Trimble Oct 14 '16 at 22:57
• Great, thanks to everyone! – Andy Putman Oct 15 '16 at 1:29
• You can search for your own deleted posted with the modifier deleted:1, so if it was your answer that is a good way to find it (this is a 10k rep thing, though). Also, in your profile there is a link on the Answers tab of recently deleted answers. – Asaf Karagila Oct 15 '16 at 5:56
• Why was it deleted in the first place, though? – darij grinberg Oct 16 '16 at 21:30
• The same thing has happened to me, both here and on MSE. One suspects the OP deliberately wanted to get rid of the evidence. – Christian Remling Oct 17 '16 at 0:39
• @ChristianRemling I didn't think the asker could unilaterally delete a question that has answers? – David Richerby Oct 21 '16 at 21:21
• @DavidRicherby : They can't delete questions that have answers with a positive number of upvotes (maybe above a certain threshold, I don't quite remember). In this case, it was deleted almost immediately after I answered, so before people had a chance to up vote. – Andy Putman Oct 21 '16 at 21:38
• @AndyPutman Oh, OK. That seems a rather undesirable "feature". – David Richerby Oct 21 '16 at 21:41
• @AndyPutman I think that it should be "with a positive score", not "with a positive number of upvotes" (example: a question with 3 downvotes and 1 upvote has negative score but a positive number of upvotes). – Federico Poloni Oct 25 '16 at 12:16