# Which question on MSE has the most failed attempts?

Half an hour ago, someone posted another answer to the question How does one prove the matrix inequality $\det\left(6(A^3+B^3+C^3)+I_n\right)\ge5^n\det(A^2+B^2+C^2)$? If this answer turns out to be wrong, it would be the fourteenth failed attempt for that question (there were nominally 15 answers at the time of writing, but one of them is actually a comment), otherwise the number is 13. This makes me wonder which question on MSE (soft questions excluded) has attracted the longest list of wrong answers.

• Browsing through this gives a good idea. I don't know if a more systematic approach exists, since AFAIK deleted posts don't show up in SEDE. – Najib Idrissi Jun 23 '16 at 11:44
• Just out of curiosity, how do you know there were 14 or 15 attempts? This didn't give me anything. This shows a list of deleted questions... – Watson Jun 23 '16 at 11:50
• Maybe this could be relevant. – Watson Jun 23 '16 at 11:54
• @Watson Users with more than 10k reputation can see deleted answers, so I assume user1551 just counted them. – Najib Idrissi Jun 23 '16 at 12:06
• It does look like this is the fourteenth wrong answer. – achille hui Jun 23 '16 at 16:01
• On MathOverflow, this question has had 17 answers, 16 of them deleted: mathoverflow.net/questions/21003/… – Gerry Myerson Jun 24 '16 at 6:41
• Take into account that a deleted answer is not necessarily a wrong answer. In most cases the converse of this will be true. – drhab Jul 2 '16 at 8:30

According to this page, here are some of the questions with the greatest number of deleted answers, and with only $0$ or $1$ answer:

Apparently, How does one prove the matrix inequality $\det\left(6(A^3+B^3+C^3)+I_{n}\right)\ge 5^n\det(A^2+B^2+C^2)$? is the winner, and Does there exist a bijection of $\mathbb{R}^n$ with itself such that the forward map is connected but the inverse is not? is the second one, with 10 failed attempts.

If you also wanted to consider "solved" (?) questions, then Evaluate $\int_{0}^{\frac{\pi}2}\frac1{(1+x^2)(1+\tan x)}\:\mathrm dx\;$ has 27 deleted answers. We could also consider this one, with 28 deleted answers, but maybe you consider it as a "soft" question...

• What about the one at the bottom with 27 deleted answers? – Tobias Kildetoft Jun 23 '16 at 12:42
• If you count questions with $≥2$ answers, then this one with 27 deleted answers has the most failed attempts. However it has now a highly upvoted answer, this is why I didn't take it into account. – Watson Jun 23 '16 at 12:48
• According to your list, technically the one with 28 deleted answers (Is $0.999999999\ldots = 1$?) wins, but I think the 27 deleted answers in the integral question are more serious attempts, so I would vote for the integral question. – user1551 Jun 23 '16 at 12:59
• @user1551 : ok, that's fine for me too! – Watson Jun 23 '16 at 13:00
• How do you know the deletions weren't just duplicate answers or a flood of spambots? – The Great Duck Jun 30 '16 at 4:25
• @TheGreatDuck: I can't see the deleted answers, sorry. – Watson Jun 30 '16 at 8:36
• – Watson Dec 16 '16 at 17:26