# Requests for Reopen & Undeletion Votes (volume 07/2018 - today)

The purpose of this thread is to help focus the attention of the community on posts that may require reopen and undeletion votes. A request should be posted as an answer below (one request per answer).

Some guidelines:

• Please be polite, and respect the many different viewpoints in our diverse community. This goes for the person making the request as well as those commenting on it.

• There is a reopen queue. Please wait until a post has gone through this queue, before posting here. Notice that the first edit after the question was put on-hold pushes the question into reopen review queue, if the edit was done within 5 days of closure. So does a reopen vote. (If the review has already been finished, it is shown on the timeline of the question.) In doubt, wait 24 hours after the last substantive action.

• To inform readers of the current (and past) states of the targeted post, please add once the request resulted in some action the information Reopened or Undeleted at the start. (If it the action is undone, add this too, like Reopened, reclosed.)

• Do not only post a request, like "request reopening of ". Instead make a case for your concern. Yet keep in mind that it can be easier to get your request handled if you try to frame in a away that takes the feedback the post received into account in a positive way rather then seeking confrontation. Also, try to improve the post before posting here.

• In case of "small" requests, like one missing vote, it can make sense to ask in chat instead of posting here. The room CRUDE is a reasonable place for such requests. The same guidelines apply there.

Earlier versions of this thread that served as a model:

Undeleted, deleted, undeleted, deleted

I nominate https://math.stackexchange.com/q/3101846/290189 for undeletion because the question asker self-deleted his question shortly after receiving an answer.

• Is that the right link? The question asker is named Jacob, which I take to be a male name, and the question was undeleted at the same time as this answer was posted. – Gerry Myerson Feb 6 at 21:03
• @GerryMyerson Nice catch! I was typing on 📱, and I made this careless mistakes. I'm going to update this status of my answer. – GNUSupporter 8964民主女神 地下教會 Feb 6 at 21:08

Reopened

Please consider reopening Indian Mathematicians. The question was closed as off-topic, apparently because of the existence of the History of Science and Mathematics site.

As I pointed out in a comment, first, questions about history of mathematics are on-topic here. The tag has almost two thousand questions and a decent amount of recent activity.

Second, the quality of many interactions at the HSM site is sadly rather poor (I was very enthusiastic about it when it started, so this poor quality quite bothers me), and it may end up being a disservice to send this question there.

(I would actually love to see the quality at that site to raise uniformly, and hope it happens relatively soon. But that is another matter.)

• I think at least the formulation of the question should be clarified a bit before it is reopened. The first answerer already misunderstood it. – quid Aug 30 '18 at 21:11
• Fair enough. I'll do a slight edit. – Andrés E. Caicedo Aug 30 '18 at 21:16
• I had decided to do an edit myself. Sorry for the confusion. I'll check back in one or two hours. If it's still closed then I'll give the final vote(s). This allows also for further editing. – quid Aug 30 '18 at 21:19
• No problem. I gave the edit a second pass. (And thank you.) – Andrés E. Caicedo Aug 30 '18 at 21:22

Undeleted, deleted, undeleted, deleted, undeleted, reopened, closed, locked, unlocked, deleted, undeleted, locked (for historical significance).

I think this question should be reopened. Thank you!

The original poster looked for the possibility to use the substitution $$t=\tan\frac{x}{2}$$ and he got a number of solutions.

By the way, the first comment of Lord Shark the Unknown is nothing. At the least, it gives a very complicated solution which the topic starter tried to apply but without success.

• Quote from the question: "I tried tangent half-angle substitution but it became too complicated." First comment on main: "Try half-angle substitution, but with a little more determination. – Lord Shark the Unknown Aug 9 at 9:54" Answer by the OP: [DNE]. – Did Sep 8 '18 at 22:17
• "By the way, the first comment of Lord Shark the Unknown it's nothing" Pfff... – Did Sep 8 '18 at 22:44
• And now there's a rollback war. – Gerry Myerson Oct 1 '18 at 12:35
• This question feels like a joke that everyone gets but me. (1) Why is this question particularly bad? The OP said they tried the obvious thing but to no avail. Presumably they made a mistake, but so what? That doesn't invalidate the question. (2) Why is there such a fierce edit/close/delete war? The question is 2 months old - let it rest!!! – user1729 Oct 12 '18 at 17:11
• Rollback to Revision 9 by Alex Francisco, rollback to revision 10 by Michael Rozenberg, rollback to 9 by Alex, back to 12 by Michael, to 9 by Alex, to 14 by Michael, to 9 by Alex, to 16 by Michael. Crazy! – Gerry Myerson Oct 15 '18 at 22:44
• This is just sorta embarrassing to watch at this point. And it's already back to 2 undelete votes, so I expect another full cycle in the next day. – user296602 Nov 27 '18 at 18:28

Undeleted, reopened

I humbly request undeletion and reopening of this question, if you see fit to do so, because

a) reasons for closing should be derived from the question itself and not from speculation about the skills of the asker.

b) the given reasons for closing are incorrect - while the question sails close to an open problem, it asks a different but related question - it asks if the open problem (which relates to a series of polynomials) can be extended to its limit point.

c) the time from entering the reopen queue to deletion was less than two hours, denying any who might have been interested in its reopening the opportunity to declare the same.

d) moreover, I think others will find the question and any prospective answers of interest and value.

• The time from entering the reopen queue to deletion may have been short, but the question had been on hold for five days already. As for the close reasons, I'll note that 2 of the close voters did not use "not math". I think that personnally I would have probably voted to close as unclear what you're asking, because on a first reading I honestly had no idea what you were talking about. – Arnaud D. Dec 1 '18 at 12:43
• @ArnaudD. Yes, but the reopen request followed an edit which increased focus on the actual question and removed the motivation for it, when I believe the question's motivation was almost certainly the cause for the down votes and closure in the first place, rather than the question itself which stands alone. – samerivertwice Dec 1 '18 at 12:47
• By the way, I think the most recent edit on your question (post-deletion) already makes the question more interesting. It only consists of adding a Wikipedia link, but that link already explains some of the context better than your question (for example, I hadn't realized that you were talking about polynomial bijections $\mathbb{N}^k \to\mathbb{N}$, but maybe that's just me). – Arnaud D. Dec 1 '18 at 12:57
• For what it's worth, the reopen review was completed before the deletion, as one can see here. – Arnaud D. Dec 1 '18 at 13:15
• @ArnaudD. good point, although predominantly the same users. Is there a better review link that shows timings etc.? I thought I saw one before but can never re-find it. – samerivertwice Dec 1 '18 at 13:39
• There's the timeline, but I don't know if it is as detailed as you'd want. (By the way, there's another question about how to find it). – Arnaud D. Dec 1 '18 at 13:44
• Setting aside all other issues, there are some obvious (and, I think, easily correctible) errors in your question's key equation, stating the F-P conjecture: the right hand side has no $y$ in it, and the index of summation $n$ appears nowhere in the expression being summed. I'm pretty sure you want the summation to go from $k=1$ to $n$, not $n=1$ to $k$, with $f_n(x_1,\ldots,x_n)$ on the left hand side, not $f_k(y)$. – Barry Cipra Dec 1 '18 at 15:28
• @BarryCipra thank-you. I think I intended $y$ to be the set $\{x_1,x_2,\ldots x_k\}$ and yes, I agree I appear to have exchanged an $n$ with a $k$ but alas no edits are allowed on a deleted post so I can't correct it :( – samerivertwice Dec 1 '18 at 18:17
• @RobertFrost That's surprising. In any case, I've just done the correction. – Arnaud D. Dec 1 '18 at 18:57
• @ArnaudD. Thanks and you even got the $f_n$ I thought might get missed. – samerivertwice Dec 1 '18 at 19:00
• What do you mean by "timings"? The time of the review is there exactly. As usual, hover over the time stamp to get a resolution to the second. – quid Dec 1 '18 at 23:44
• @quid thank-you. That probably covers it although I can only see a deleted post on desktop so I'll have to check later – samerivertwice Dec 2 '18 at 4:07
• @ArnaudD. Thank-you for the edit. A reopen vote would be greatly appreciated (only if you think it appropriate). Else the deleters will reverse the undeleters! – samerivertwice Dec 3 '18 at 10:39

Can this answer (on permutation groups) be undeleted:

https://math.stackexchange.com/a/3197094/10513

It was deleted for not providing an answer to the question. However, it gives a decent hint which leads to a solution. The hint is essentially "consider odd vs. even numbers". This was made formal in the accepted answer, which used mod 2.

• I think it's a bit of a stretch from that hint to the accepted answer. The hint ought to be a comment (in my opinion). – Gerry Myerson Apr 29 at 12:50
• @GerryMyerson Hints are a grey area. But I don't think deleting them because they are "a bit of a stretch" is the right thing to do. – user1729 Apr 29 at 12:55
• It would have been better, had a moderator converted the "answer" to a comment. You could try flagging the question for moderator attention, and making that suggestion. – Gerry Myerson Apr 29 at 12:59
• I flagged it beforehand, and was told to post my request here (admittedly i didn't suggest making it into a comment) – user1729 Apr 29 at 13:19
• OK, now you know what to do. – Gerry Myerson Apr 29 at 13:22

Undeleted, Merged and then deleted

Please reopen https://math.stackexchange.com/q/3208119/290189 since OP has self-deleted his/her own post after getting an answer. The community should have been given enough time to vote.

• You can't reopen a question that isn't closed, GNU. Now it has been closed, as a duplicate, but I don't see how $x^y+y^x=(xy)^2-19$ is a duplicate of $x^y-y^x=xy^2-19$. So, I'm flagging for moderator attention. – Gerry Myerson Apr 30 at 13:47
• @GerryMyerson By the moment I posted this answer, I did voted to close this question as missing context. I did notice the difference between the two. Thanks for reminding me. – GNUSupporter 8964民主女神 地下教會 Apr 30 at 13:52
• @GerryMyerson a problem is that the original version of the question was incorrect. A third party edited it to this version, while main OP had re-asked a different version. – quid Apr 30 at 15:32
• I deleted it after the merge now. This did not work out ideally, but it's near impossible to fix. If somebody wants that version of the question on the site I recommend to ask it anew. – quid May 2 at 18:17

Deleted, undeleted, deleted, undeleted, reopened

Please reopen Calculating the summation$$\sum_{n=1}^{\infty}\frac{H_{n+1}}{n(n+1)}$$ because it's not an elementary question and OP has tried checking the proposition using Wolfram Alpha.

• In my opinion it's very poor style to reignite this after month without mentioning any of the earlier activity in which you even were involved. Thus, I locked the post for now. – quid Apr 30 at 11:43
• I'm puzzled. A "content dispute" notice was lifted in March 2018. The content has not been altered since then. So it seems strange to lock it for "content dispute" now, @quid. [I guess I should mention that I was involved in earlier activity.] – Gerry Myerson Apr 30 at 13:56
• @GerryMyerson Are your really puzzled or are you just searching an argument? First, the content of the post was also not changed between the first locking and the first unlocking. Second, the lock was not lifted in the sense of somebody lifting it, it simply expired. It was not reinstated as there seemed no need back then about a year ago. Then half a year ago, there was one more round of undelete-delete but it fizzled out quickly. Now somebody wants to go back to this again, indeed without any further changes, simply picking up the del-undel again. To prevent this, I locked it. – quid Apr 30 at 14:36
• Third, it might be relevant to note that the lock was "lifted" while the post was deleted. Thus, if consistency is the concern of course I should lock it again now. I could also have it become undeleted and then personally delete it again. Last time around some where keen on locks being used. So, there you go. Of course that's not fine for you now either, presumably because it does not cater to your personal preferences. – quid Apr 30 at 14:43
• To sum up, I locked it to prevent the delete-undelete cycle being restarted. By now the question was deleted four times. Plus it is an odd situation, in that it first got siginificantly improved by a third party only for this then being undone If anything should happen likely a completely new version should be posted. This would be a reasonable thing to do if preserving content is the actual goal. Of course if playing un-del games should be the goal... thus locked. @GerryMyerson – quid Apr 30 at 14:48
• @quid, when I write that I am puzzled, please do me the courtesy of accepting that I really am puzzled. I'm puzzled not so much by the locking but by the phrase, "Content dispute", when there was no change in content. Had the locking notice said "Prevent delete/undelete cycle" I don't know that I would have made any comment. Does a moderator have the option of inserting custom-made locking notices, or is "Content dispute" the only phrase available? Also, I always assumed that when a moderator locked a question, the question stayed locked until a moderator decided it was time to unlock it.... – Gerry Myerson Apr 30 at 22:46
• ....I didn't know that locks expired of their own accord after a week. I've been here almost a decade, and I'm still learning how the place works. – Gerry Myerson Apr 30 at 22:47
• @GerryMyerson the list of reasons is fixed (we can ask for additions in principle but not spontaneously) "content dispute" is the one commonly used in this case, others are "off topic comments", "contest question", "cw answer", "historical significance". We can lock for an hour, for a day, for a week, or permanently. Usually one tries to avoid permanent locks. – quid Apr 30 at 23:58
• Probably it's worth mentioning that there already is one answer in this thread about the same question. – Martin Sleziak May 15 at 7:34
• @quid, thanks for the explanation about length of locks. It's not possible, is it, for non-moderators to see what length a moderator has chosen when that moderator locks a question? – Gerry Myerson May 20 at 4:26
• @GerryMyerson indeed I think that's not possible. – quid May 20 at 8:39

Please unmark the duplicate of this question. I have clearly said that my question has nothing to do with duplicate one. I am asking totally different thing and the duplicate question's answer does not help me at all. It is also an unique question which follows m previous question.

• I don't believe the relationship between the Questions is quite so simple as one "has nothing to do with" the other. Both involve intersections between two spherical caps, although you might not have visualized your problem in this way. There might still be a further problem in stating the area in terms of how you parameterized the spherical region, I grant, but it would be worth understanding the solution of the proposed duplicate to try restating the area given there in your terms. – hardmath Jun 6 at 17:11

Undeleted, closed, deleted, undeleted, redeleted

I nominate Solve the recurrence $$\sqrt {x_n} − 5 \sqrt {x _{n−1} }+ 6\sqrt {x_{n−2}} = 0$$ for undeletion because OP has self-deleted his post shortly after receiving an answer. That's rude to the answerer.

• I agree that the question should not have been deleted by the original asker, and would have voted to undelete had I seen this before the question was undeleted. That being said, it is a pretty low quality question, and would like to now nominate it for closure and (if it is not improved) eventual deletion. – Xander Henderson Nov 12 '18 at 23:26
• @XanderHenderson Agreed and updated the status of my answer. – GNUSupporter 8964民主女神 地下教會 Nov 13 '18 at 1:27
• It is inconceivable this question is undeleted. Even the answer is pretty low-quality. – YuiTo Cheng Jun 26 at 4:53
• I find that revision history really surprising : one (now removed) user voted to undelete and then close the question, OP initially self-deleted the question but 5 days later voted to undelete after the second deletion, and now you've voted to undelete and then redelete the day after. Pardon my French, but WTF? – Arnaud D. Jun 27 at 9:31

Undeleted, reopened

Please consider undeleting and reopening this post:

where OP gave his/her thoughts:

Honestly I have no idea about how to approach this problem. I tried the expansion of $$\sin x$$ on the left hand side and then expand $$\cos x$$ on the right but end up with a mess. Then again $$\cos x=(\sin x)'$$, but by converting each term on the right hand side into derivative of sine does not give any sensible identity to draw out something. Really out of ideas on this one. Is there any way to do this? Please give me some hints. Thanks for your time.

Undeleted, deleted, undeleted, deleted, undeleted, reopened

Please consider casting the final undelete vote and reopening this post:
Evaluate $$1+2-3-4+5+6-7-8+\cdots+50.$$

This question is well written and with effort. It has very well written answers, one of which gives a generalization of the problem.

Please consider undeleting and reopening this elementary question: On proving $$\sum_{k=1}^{2^n+1} \frac{1}{k} > \frac{n}{2}$$

OP had his/her thoughts on the problem and also added an attempt for verification in the post after interaction in comments with others. This question has also been edited.

Reopened, closed

Please consider reopening (also for the sake of avoiding further unreasonable strong action of deletion, there has been a delete vote already): How to show for $$x\in \mathbb{R}$$, $$|x|\leqslant 1+x^2$$

This is completely a legitimate question to ask for a beginner. Also, OP did show his/her work in the post, although he/she did not notice what he/she proved is actually a stronger result. Furthermore, it has very well written answers.

I feel it very harsh to close/delete such posts.

Undeleted, deleted, undeleted, reopened

Please undelete On a colon ideal in the polynomial ring $\mathbb R[x,y]$ because this question has got a score of 2 after OP included his/her own thoughts on the problem. This algebraic geometry question might add value to the main site.

• Selfdeleted without answer. No need to undelete. – quid Feb 25 at 9:16

Undeleted, redeleted, re-undeleted, redeleted, undeleted

Please consider undeleting the question: The asymptotic behavior of $$n\ln n -n$$

• Well, I'd consider something in the spirit of the comment as the best answer there. Anyway given the complete lack of context it's hard to know which type of answer would be useful, whence the voluminous list. Also all standard likely on the site in similar form tens if not hundreds of times. At least one answerer made the effort to link it to related posts. – quid Jun 6 at 22:37
• Redeleted (6/17/19) by a same group of users. One initiated three times the delete votes and one voted three times to delete this post. – Jack Jun 17 at 22:01
• Probably I should have refrained of posting an answer there - however at the time when I posted there were some answers already and they seemed (to me) more complicated than needed. I have also included links to some other questions - you can see that similar questions are on the site (and they have similar answers). I will also say that when posting the answer I was fully aware that the question is likely to be closed/deleted. – Martin Sleziak Jun 18 at 17:35
• @MartinSleziak: I believe "closing" is enough for this particular post. I strongly disagree with the deletion considering the high qualities of answers. Such good contents will be useful for future readers (this is closed post is not some stupid trivial textbook exercise) and should be preserved on the site. – Jack Jun 28 at 12:22
• @Jack Well, several discussions here on meta suggest that when deciding about closing (and probably also deleting), most users take into account mainly quality of the question (and do not look at answers). Since you have mentioned that you care about preserving context, I should specifically point out that my answer contains some links to other posts which use Stol-Cesaro. Will Jagy reposted his answer in another thread. (For obvious reasons, I might be a bit biased in this particular case.) – Martin Sleziak Jul 6 at 17:55

Please consider undeleting this post: Integral $$\int_{0}^{2\pi} \ln (2\sin(\frac{x}{2}))dx$$

Whether the asker should articulate more details in "I've tried some substitutions" could be debatable for reopening the post; I do not think it should be deleted. There have been two answers, one of which has 11 upvotes.

• The question was on hold for a week without modification before it was deleted. The answers are fine, but standard, and don't rise to the level of exceptional. I see no reason to undelete this question. The asker clearly got what they wanted, and I don't see that question providing any lasting value to the site. – Xander Henderson Jul 2 at 0:46
• The lasting value to the site, like many other posts, is that there are two good answers to a tricky calculus question, which is not only useful for the asker but also future readers. – Jack Jul 2 at 1:48
• The first part of your reply to me does not contradict what I said: you say that there are two good answers, I said that there are no exceptional answers. As to use to future readers: I disagree. This is a specific integral which can be analyzed using relatively standard techniques. The question itself is not terribly searchable (it is only going to come up if someone wants to deal with that specific integral (e.g. they are assigned the same problem as a homework exercise, and are trying to cheat), and the answers are not of any general interest (they are standard, but not general). – Xander Henderson Jul 2 at 1:53
• Disagree. "This is a specific integral which can be analyzed using relatively standard techniques. ... the answers are not of any general interest " does not justify the deletion. MSE is not MO: most, if not all, of questions here "can be analyzed using relatively standard techniques". For instance, this recent question that has two good answers, the accepted one written in detail nicely by you, is a rather "standard" one. I would certainly not vote to delete such posts. (In case of any possible confusion: this is NOT sarcasm.) – Jack Jul 2 at 2:48
• It is funny that you pick that example. I downvoted that question, and voted to close it. It was not closed, and the other answers were, in my opinion poor answers (as they failed to address the key point, which is that an induction proof is needed somewhere). If the question is not going to be closed and deleted, it should at least have a correct answer. I would still be happy to see that question closed, and would not object to its deletion---my answer is nothing special, and doesn't (IMO) rise to the level of exceptional. – Xander Henderson Jul 2 at 2:56
• Moreover, applying standard results to a specific problem is very different from demonstrating the correctness of standard results then leaving it to the reader to apply that result to their specific problem. – Xander Henderson Jul 2 at 3:01
• Well, (1) I have done my proposal for undeletion. Readers can make their own decisions. (2) I will object strongly the post I just mentioned being deleted, considering the quality of your exposition and egreg's good answer. (How do you find the review history by the way?) (3) ... have to leave now. – Jack Jul 2 at 3:13
• Probably a duplicate of one or more of math.stackexchange.com/questions/815762/… and math.stackexchange.com/questions/889902/… and math.stackexchange.com/questions/679233/… and math.stackexchange.com/questions/2656431/… and also comes up in any question containing the name "Clausen". – Gerry Myerson Jul 2 at 3:20
• @Jack To find the review history I go to the timeline of the post and then click on the link to the review event there. I don't know if there's a quicker way. – Brahadeesh Jul 2 at 6:41
• @GerryMyerson: having read your links one by one, I would probably not called the post a duplicate of those, although they are related to the Clausen function. (Never known this before, thanks for mentioning it.) – Jack Jul 2 at 11:47
• @Brahadeesh: Thanks for that. One can indeed use math.stackexchange.com/posts/3143084/timeline – Jack Jul 2 at 11:56
• It's funny how those who voted to close/ delete are here on this site for a while, and even claim to know that the question is easily searchable. Yet, instead of trying to mark it as duplicate, they simply delete it. Also it's quite bold for a single group of people (CRUDE users) to decide that it has no value for this site. – Zacky Jul 22 at 8:50
• @Jack would you be interested to help, if a chat-room to counter CRUDE people's rampage to delete such questions would be created? – Zacky Jul 22 at 8:51
• @XanderHenderson I wrote above in the third person since you're not the only one who believes that, but since you commented it here, can you please tell me why haven't you tried to mark it as duplicate (if it's easily searchable) and simply decided to remove the content? (maybe there's a reason that I'm missing). – Zacky Jul 22 at 8:58
• @Zacky I have previously commented that the first question one asks should be "is this a good question?" If the answer is "no", then the question should be closed and deleted. If the answer is "yes", then it is worth looking for dupe targets. This question is not a good question, so it was rightly closed and deleted. Moreover, I don't see anyone claiming that dupe targets easily searchable, only that the answers use standard techniques, and do not rise to the level of "exceptional". – Xander Henderson Jul 22 at 13:27

Undeleted

Please undeleting this post: How to prove that $$\frac{e-1}{2e} \le \int_0^1 \frac{e^{-x}}{1+x}dx \le \ln 2$$

OP did have his/her own attempt. This is not a zero-effort trivial question, which should not be deleted.

Undeleted, deleted, undeleted, reopened, closed as duplicate (mod)

Please consider undeleting this post: 2011 IMC Section A Problem 3

This is not an ongoing contest problem. The answer is known online. @Aqua's answer (with 14 net upvotes) is a useful one.

• Poorly explained answer. Had downvoted it back then. – quid Jul 6 at 19:53
• That was a really bad excuse for deletion. – Jack Jul 6 at 21:09
• Since I did not delete it, I don't need any excuse (and I doubt the delete-voters where aware of my voting back then). Please do not write comments that might suggest otherwise as not everybody can check it easily. – quid Jul 6 at 22:20

I nominate https://math.meta.stackexchange.com/q/29570/290189 to be undeleted because this meta question contains moderator's feedback to deal with serial downvotes.

• What information is in that post that is not in the FAQ? Also as it was auto-delered it'd be redeleted. – quid Feb 9 at 12:46
• @quid That post provides real examples of questions being serial downvoted. – GNUSupporter 8964民主女神 地下教會 Feb 9 at 12:48
• How is that useful? – quid Feb 9 at 13:14

Deleted, undeleted, redeleted and merged with another question

I request the undeletion of this question (on denesting $$\sqrt{a-b\sqrt{c}}\,)$$

Reason: I asked this question, and it turned out to be a duplicate. However, this doesn't deserve deletion as this question contains a crucial formula that is a very useful one. It is very useful to me, and it is sad for me to see that the community is not able to access it anymore. Please undelete this question.

• The answers there are dupes of the answers in the linked dupe thread (and many others - this is a FAQ). I see no reason to further such rampant duplication. – Bill Dubuque Mar 1 at 1:03
• @BillDubuque there is a useful formula. Perhaps if you can transfer the answer to the other question?? I find it really useful. – Max0815 Mar 1 at 1:04
• That well-known formula is already in Frank's answer in the dupe (and many, many other answers here). Moreover, he derives if instead of pulling it out of a hat as in the answer in your thread. – Bill Dubuque Mar 1 at 1:06
• @BillDubuque how is it derived? even if so, the other answer on my question has a basic method that is not included in the other question. – Max0815 Mar 1 at 1:08
• @BillDubuque oh, right. – Max0815 Mar 1 at 1:11
• I don't understand why this question was deleted. It seems to me that the only reason is that it is a duplicate. I do not believe that this is a reason to delete duplicated (and this was discussed recently here). – user1729 Mar 7 at 13:10

I would like to see this question undeleted and mark as duplicate but keep it alive on the network.

Also, I object to the deletion since although the questions are looking for the same thing, I must mention that they are not word by word duplicates and the context also seems a bit different. Also, the answers are not duplicates (except one which coincidentally was answered by the respective OPs of both questions).

• This question was deleted by a moderator, which means that only a moderator can undelete it. As such, there is pretty much nothing that anyone here can do for you. – Xander Henderson Apr 5 at 17:50
• @XanderHenderson I posted this on meta. Someone asked me to post here (just to be shot with 3 odd downvotes here ) – tatan Apr 5 at 18:54
• Votes on meta do not mean the same thing that they mean on the main site. A downvote means "I do not agree with this statement." I would interpret the downvotes here as an indication that the community does not want to reopen / undelete your question. – Xander Henderson Apr 5 at 20:50
• @Aloizio Macedo can you please give some reasons on why you single-handedly deleted the question? (as it stands it looks like an abuse of power, but maybe there'a reason that I'm missing) – Zacky Jul 22 at 9:16

Undeleted, closed, re-deleted (not by question-asker this time)

Please reopen https://math.stackexchange.com/q/3129981/290189 because the question asker has self-deleted his/her own post after getting an answer. The communnity has not got enough time to judge its value.

Please undelete https://math.stackexchange.com/q/2192864/290189 because OP has self-deleted his question one minute after receiving an answer from me. This is an abuse of the system.

• OP shouldn't have deleted it, but what a miserable excuse for a question! With all due respect, I don't think you should have answered it, not without first getting OP to bring it up to standards. – Gerry Myerson May 24 at 2:47
• The question was deleted one minute after receiving an answer, but this request was posted more than two years later. If the asker deleted the question to cover up the fact that they got help, then they already succeeded. I don't really see a reason to undelete this, because it would just get closed and deleted again. – user296602 May 24 at 6:42
• The relevant rule is this: "Before voting to delete, please check whether there are any good answers; [...] We don't like to lose great answers!" By voting to delete the question, you violated this rule. – peterh Jun 1 at 17:00
• I disagree with the way Xander disagreed: "I see no reason to undelete this question in it current form". I disagree with the deletion as I would disagree with (potentially possible) close/deletion of this question Xander answered: math.stackexchange.com/q/2414862 – Jack Jun 1 at 17:16
• @Jack I have no problem with the closure of the question to which you linked. I do find your targeted citing of that question interesting, and would note that when I answered that question, I had been active on MSE for a grand total of 2 months, and had not yet learned the norms. If I saw that question newly posted today, I would likely very quickly vote to close. – Xander Henderson Jun 1 at 17:28
• Normally when posting here, one is expected to put in an explanation for why this question should be undeleted, reopened, etc. The boldface line on the top is meant to indicate the status changes after posting, and not be a part of the request. – Asaf Karagila Jun 1 at 17:28
• @XanderHenderson: "I have no problem with the closure of the question to which you linked". Sorry I do. I would disagree with closing the question you answered nicely I linked and in particular I would strongly disagree with deletion of that linked post. I do not think there was/is a "norm" for deletion so far for the site except the general rule peterh quoted in a comment. – Jack Jun 1 at 17:30
• @quid I was impressed on them. It is subjective. But their score is objective. – peterh Jun 1 at 17:45
• For moderator who keen on different opinions/ideas from his/her own by MSE users: "Please don't abuse your power to stir discussion up when users disagree with your (possibly not so wise) idea of deletion and 'and respect the many different viewpoints in our diverse community' ". – Jack Jun 1 at 17:51
• @peterh: I don't see how that situation on server fault is "similar". And again, I'd ask you to avoid using inflammatory language. It helps no one, except perhaps you, to release pent up anger. It's inappropriate, and deteriorates the remote option that anyone is going to have a discussion. – Asaf Karagila Jun 1 at 17:54
• @Jack so how about you respect others views or at least the rules of the site. – quid Jun 1 at 17:54
• If you think that this is somehow similar, you should spend a bit more time trying to learn the underlying software, the system of privileges, and what is the job of the moderators. – Asaf Karagila Jun 1 at 17:57
• @peterh the discussion is on-going since years. Just this morning I spent an hour with an other user to analyze data about this. Users (as opposed to moderators) are severely rated limited as concerns deletions. That you are miffed because three of your posts were deleted, does not mean that there is some problem. Yes, some users are against deletions, but again that's true since years. Maybe focus more on following rules regarding questions quality, then the issue regarding deletions will be of much less relevance. Don't cherry pick rules. – quid Jun 1 at 18:15
• @quid It is your decision, what will be a mod issue. I need to notice, too, this sequence of events: 1) one of my old posts is deleted, in my opinion, falsely. 2) I complain on the meta. 3) The post gets an undelete and a reopen. 4) 2 of my old posts are deleted. | I think, the nicest possible interpretation is that my meta post attracted some attention to my old main site posts. The lesser nice, but maybe more likely interpretation is that these were revenge deletions for my complains. – peterh Jun 1 at 18:44
• @peterh the short questions are not blindly deleted but they are reviewed for potential deletion. Well your question has 0 score [correction: -2 now], which leaves use were exactly. Five users thought they want the question closed. Maybe there view also should count for something. Of course they did not all bother to dv in addition, but there opinion seems to be clear. Kindly stop the cherry picking and the quoting of half-sentences. However you want to frame it, the thread is not good. Also the high score is a high quality is a gross over simplification, as everybody knows. – quid Jun 1 at 20:04
• @peterh people evaluate your post and find it lacking. Of course you can pretend it's for other motives, but then way back then it was already closed. That some users upvoted the answer does not change that. It's well-known that often almost obvious stuff is especially well received because there are enough voters that can easily make sense of it. Again the answer is not good in the way I believe good is intended there. It's a correct yet completely standard answer to simple and contrived question. The site is better without that thread. – quid Jun 1 at 21:53
• I have edited the post (revisions, the version after my edit) in order to add at least some context. I have not case my undelete vote - I'll wait first to hear whether you are satisfied with the edit and leave some time for you if you want to edit it further. – Martin Sleziak Jun 3 at 5:16

Undeleted,reopened

+6 question with thousands of views and with two, +18 answers. Created in 2016, deleted last week.

Found by the SEDE query Suspicious question deletions from the last week.

• Standard solve-my-problem-without-me post, and nothing spectacular about the answers. I oppose undeletion. – user296602 Jun 3 at 10:29
• @T.Bongers To me, it is absolutely non-trivial, if the sum of a singular and a nonsingular matrix is always nonsingular. The example in the accepted answer was catartic to me. Your attitude would be probably acceptable on the MO, but that is another site. Here sub-phd, maybe even pre-grad level questions are allowed, and you should view the quality and usefulness of a question on the level for which it is written, and not on yours. – peterh Jun 3 at 10:38
• I have no idea at what level the question was written (and neither do you), because the asker never bothered to say anything at all beyond the statement of the problem. This is not a do-my-homework site, regardless of how little quality control some users want. – user296602 Jun 3 at 10:44
• @T.Bongers Maybe the user 1) is enough educated to be able to think about, is the sum singular and nonsingular matrix always nonsingular 2) But he is not enough well educated to know its answer? Is it enough narrow to know, who is he? Hm? Or should he have attached his CV to his question as well? – peterh Jun 3 at 10:47
• This isn't a case for some hyperbolic slippery slope argument, and you know that. If the question had context, it could be appropriate for the site. – user296602 Jun 3 at 10:51
• @T.Bongers The required "context" what you would want so strongly, is clearly visible in the post. And you know that. This is a typical case of the dark direction what you made from this once so friendly and open site. – peterh Jun 3 at 10:54
• I disagree with T.Bongers's comment: "Standard solve-my-problem-without-me post..." In what "standard", if exists at all, for a site "that is for people studying math at any level and professionals in related fields"? I disagree with the deletion in a way that I would strongly disagree with (possible in the future) deletion of this and this "standard" exercises (created 2016 and 2018) T.Bongers answered (nicely!). – Jack Jun 3 at 11:55
• @Jack Thanks for bringing those posts to my attention; I agree with your judgement of the first one (but not the second), and have started a close vote. I would delete my answer if I could, but it was accepted. Of course, it's clear that your comment is a disingenuous off-topic attempt to poison the well by calling me a hypocrite. So it goes. – user296602 Jun 3 at 12:15
• @T.Bongers: Thank you for your message. "it's clear that your comment is a disingenuous off-topic attempt to poison the well by calling me a hypocrite." Please don't put any word into my mouth that I did not say at all. I am sorry that you think it in that way. I do mean what I said and I do NOT mean to be sarcastic at all. Since we are talking about "deletion", I don't think my previous comment is off-topic. And yes, if you or others were going to vote to delete the linked posts that you answered, I would disagree and vote to undelete. – Jack Jun 3 at 12:48
• I'd like to remind everyone to keep it civil. – Asaf Karagila Jun 3 at 15:17

I think we need to open the following Mike Lyons's answer: The smallest value of $$x^2 + 5y^2 + 8z^2$$ such that $$yz+zx+xy=-1$$

I think it's a beautiful and right answer. We need to redact it only.

It was my mistake to delete this answer.

• Note that the question has since been deleted. – Gerry Myerson Oct 9 '18 at 22:27

Ratio problem for aptitude exam in India [closed]

None of the questions was eligible for a deletion, and also their closure reason is highly problematic.

• If the question was not eligible for deletion then how, pray tell, was it deleted? The question itself is nothing more than a problem statement, with only minimal context given (it is from some Indian aptitude exam). The question is unmotivated, and there is zero evidence of any effort having been made to answer the question. I see no reason to undelete. – Xander Henderson Jun 1 at 16:39
• As an addendum, I find your demanding tone to be unpleasant. It is your opinion that this question, and the one you linked to above, should be undeleted. It is your opinion that they should be reopened. It is your opinion that no valid deletion reason exists. Clearly, others disagree with you. Demanding that others take some action is unreasonable. Make a request, make your case, then wait for the community to decide. – Xander Henderson Jun 1 at 16:42
• I have no demanding tone. I see a content deletion rampage, targeting particularly me, possibly as a revenge action for my recent meta post, where I complained another rule violating content destruction. What you can see now, is that I try to do something about it. If it is "demanding tone" for you, let it be so, but it is not a reason to me to do anything differently. – peterh Jun 1 at 17:03
• @peterh Your phrasing "Needs undelete, possibly reopen, no valid deletion reason exists" is very aggressive and demanding, and stating that no valid deletion reason exists is rather dismissive of the people who disagree with you. A lot of the site functions well because of consensus, not dismissive attempts at solo decision-making. (-1) from me, because I think this is a bad question to keep on the site. – user296602 Jun 1 at 18:14
• @T.Bongers Please check the end of the other discussion. I not only complained, I also analyzed SEDE data. I invested this effort because 3 of my old posts were deleted within days, what made me suspect that it was not pure coincidence. In the current discussions, I've seen only little arguments that the posts were really bad, however the relevant rules explicitly forbid the deletion of questions with good answers. – peterh Jun 1 at 18:33
• @T.Bongers From here: "Before voting to delete, please check whether there are any good answers; [...] We don't like to lose great answers!" – peterh Jun 1 at 18:34
• @peterh It says: "Closed questions that are of no lasting value whatsoever should be flagged and deleted." Thus, explain the lasting value of the post. Same for the other question. As far as I can tell there is no lasting value. It might be nice that you helped that other users even though they did not follow the rules regarding question quality, but lasting value, there isn't any. – quid Jun 1 at 18:46
• @peterh At least eight different experienced voters here think that the question is worth closure or deletion. Perhaps you could spend some time thinking about why that is, instead of just rules-lawyering to get the answer back. – user296602 Jun 2 at 3:41
• @T.Bongers My problem with your this comment, and with your attitude, that after the removal of the argument from authority part, nothing remains. Only a bunch of revenge votes. – peterh Jun 2 at 3:53
• @T.Bongers It is interesting! I worked a lot on the answer. Only that a problem is not interesting you, is not a reason to click delete. Actually, doing that is a power misuse. There should be clear rules, what makes a question deletable, none of them was mentioned. – peterh Jun 2 at 5:18
• @GNUSupporter8964民主女神地下教會 Btw, my these whole current activities were initiated by the following sequence of events: 1) some of my posts were closed and deleted on crap reasons. I remained silent that time. 2) yet another of my old posts were deleted. I initiated a discussion on the meta. 3) Two another of my old posts were deleted. It was clearly a revenge action from the 10k+ side. | Deleting posts by revenge votes is clearly one of the most serious power misuses, and should be punished harshly. However, the mods looked elsewhere, and said "no proof". --> this was the point as I started – peterh Jun 14 at 11:30
• @GNUSupporter8964民主女神地下教會 my current activities, and I won't stop. I have the right to use the site as it should be used, I find it an ignorable surreality if you call this "rep farming", and I will fight the retroactive, massive content destructions until my last breath. So is it going, I am sorry. Downvoted posts don't deter me. Deleted posts don't deter me, I use them as examples of your hostility. The only what would deter me if you could somehow convince me, that what I want, is no good, but I think it will be a hard work. – peterh Jun 14 at 11:31
• @GNUSupporter8964民主女神地下教會 After my comments yesterday, you've deleted my yet another answer, and I've got 5 downs. It all happened to my old posts. You are just a dirty mafia, and you have exactly zero moral base to complain any "rep farming", while you are downvoting and deleting main site posts as revenge, for unrelated meta activities. – peterh Jun 16 at 6:52
• @GNUSupporter8964民主女神地下教會 I know very well, why. And also you know the "why" very well. I will continue this discussion if you stop playing the fair one, while your revenge actions are clearly visible. | Btw, the mods seem relative inactive in such infights, compared to other sites - on other sites, they had already probably intervened for my vehement style. However, they had probably intervened also for your retributive, revenge actions. – peterh Jun 16 at 9:47
• @GNUSupporter8964民主女神地下教會 Oh yeah, of course "no revenge"... – peterh Jun 17 at 8:59

## protected by Community♦Oct 1 '18 at 14:49

Thank you for your interest in this question. Because it has attracted low-quality or spam answers that had to be removed, posting an answer now requires 10 reputation on this site (the association bonus does not count).