# 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:

Reopened

(This is to break this request post into two)

I would like, if it is possible, remove the labels close-hold for some of next of my recent post Convergence of $$\prod_{n=2}^\infty\left(1-\frac{1}{n^2}\right)^{i^n}$$, where $$i$$ is the imaginary unit

I think that the answers are very interesting and very good, and I think that the questions are in the standard of questions of MSE. Any case many thanks.

Undeleted

I nominate Is the Balazard-Saias-Yor integral non-positive? for un-deletion and re-opening. Being self-deleted by a deleted user, it has a score of +1 and two stars. The topic adds value to the site and the question asker has put effort in the post.

Currently, only one undelete vote is needed to undelete this question. I hope the two users who starred this question can see their favorite question re-opened.

• It should be noted that "stars" do not necessarily indicate that a user finds the question useful or up to the standards of the site. Many users use stars to keep track of questions with which they have interacted, and desire to return to at some point. For example, I sometimes star questions which lack context or otherwise fail to meet the standards of this site. After downvoting, leaving a comment, and/or voting to close, I will star the post so that I can return to it a few days later to see if it has been improved. If it has, I'll retract my downvote and/or close vote. – Xander Henderson Feb 4 at 17:02
• I'm not saying that this is the case here; I just want to point out that "stars" should not be taken as a sign of quality vis-a-vis undeletion votes. – Xander Henderson Feb 4 at 17:03
• @XanderHenderson Thx for comments. Noted. – GNUSupporter 8964民主女神 地下教會 Feb 5 at 1:27

Please reopen The characteristic polynomial of $A$ is $x^n$ if and only if $\text{Tr}(A^i)=0$ for all $1\le i \le n$. due to the reasons listed in OP's comment. The first duplicate matches half of the question. The hypothesis of the second duplicate is different from the first one.

Deleted, undeleted, deleted, undeleted, deleted, undeleted, deleted, undeleted and closed

unfortunately the question I asked Why is the zero polynomial the only one to have infinite roots? was put on hold as off-topic first and then closed. I edited it much for it to be reopened but it wasn't opened. I apologise if it was off-topic to you, but I edited it. If it being off topic yet, kindly suggest improvements or reopen it.

• Please include a link to the question. – quid Feb 3 at 14:54
• its humble request – user629353 Feb 3 at 14:56
• why you deleted that – user629353 Feb 3 at 14:58
• @quid couldn't you suggest edits – user629353 Feb 3 at 15:03
• "couldn't you suggest edits " What do you mean? How am I supposed to know which question you mean? – quid Feb 3 at 15:05
• @quid the link of which i have given above – user629353 Feb 3 at 15:09
• I misunderstood what you meant. I did not delete you question. At the moment I do not plan to get involved. – quid Feb 3 at 15:46
• Two posts here about the same question. Are we supposed to expect some more any time soon? – Did Feb 3 at 21:39
• @Did, the first post was about closure, the second, deletion. Unless there is some action more severe than deletion, I'd guess there won't be any more posts about the question. – Gerry Myerson Feb 3 at 21:52
• I have flagged the question on main to ask the moderators to let the community make the decision. – Gerry Myerson Feb 5 at 11:48
• The main problems with the question seem to be that (i) the questioner is confused, and (ii) it's tricky to answer in a way that properly addresses the confusion. The first seems a good reason to ask the question, and the second suggests that good answers will be thoroughly explanatory and therefore of high value. – timtfj Feb 5 at 16:05

Undeleted and merged with duplicate

I would like to see the question "Finding sum to infinity" undeleted. The OP says that they "tried using the Taylor series for $$e^x$$ but couldn’t figure out how to manipulate it to get the above expression", which seems reasonable. Moreover:

1. The question is a duplicate and is closed as such. It is not standard practice to delete duplicates (see here).
2. The question itself is on +5 (+6/-1), and one of the answers is on +12.
• I don't get the argument. What is the value of keeping that question on the site? – quid Feb 15 at 19:00
• I didn't realiize that "it is standard practice to not delete duplicates." Cite? – Gerry Myerson Feb 16 at 4:06
• @GerryMyerson I also had entertained to comment on that. What arguably is true is that "it is not standard practice to delete duplicates", which of course is not quite the same. – quid Feb 16 at 12:14
• @Gerry What I meant was "a question should not be deleted simply because it is a duplicate" (so I've edited the post to quid's sentence). This was discussed here. – user1729 Feb 18 at 11:28

Reopened

Please undelete Generalization of the fundamental theorem of duality since the question asker has deleted his/her own question shortly after receiving an answer. This is an abuse of the system.

Undeleted and reopened

Please reopen Proving the greatest lower bound. because OP has self-deleted his/her own question after I've answered this question. This inhibits the community from viewing the question.

Reopened

Prove $\lim_{z \rightarrow z_o} f(z) \in \mathbb{C}$ if $\lim_{z \rightarrow z_o} (z-z_0) f(z) = 0$

I made a new question, where I tried to be as clear and narrow as possible.

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

I nominate A question of arithmetic regarding erection cost of a structure. for reopening since the question asker has shown his/her work in solving the problem.

• I agree, but think they should also be encouraged either to edit what they said in comnents into the question, or to give someone else permission to do so. – timtfj Feb 5 at 12:20

Undeleted

I nominate Optimization problem for routes 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 Is there an injective homomorphism from $S_4$ to $GL(2,C)$ because the question asker has shown efforts in solving the problem, and it has a score of 4 with an accepted answer of score 3 from a 25k user.

• Answers should not be used to judge whether a question should be reopened. But in this case, the asker did include sufficient context, so that's irrelevant. – user21820 Mar 25 at 9:44
• "Answers should not be used to judge whether a question should be reopened." That's your opinion, @user – it is not a rule, or even a consensus. – Gerry Myerson Mar 25 at 11:51
• @GerryMyerson: It is your comment that is an opinion; it's not even a consensus. Both this and this clearly demonstrate a consensus that "bad questions beget bad questions" and "closed questions can and should be deleted even if the have good but standard answers; only truly great answers should rather not be deleted". – user21820 Mar 25 at 12:37
• @user21820 Thanks for your comment. I'll be aware of that next time. – GNUSupporter 8964民主女神 地下教會 Mar 25 at 16:39
• @user, your quote refers to deletions, not closure/reopening; what's more, the part that says "only truly great answers should rather not be deleted" plainly contradicts your assertions that "answers should not be used to judge...." – Gerry Myerson Mar 25 at 21:51
• @GerryMyerson: Firstly, if a bad question ought to be deleted, then obviously it should not be reopened. Secondly, it would be real silly to assume that everything I say is to be taken completely rigidly with no room for exceptions; from my very first comment I meant that as a rule of thumb answers should not be used to judge... – user21820 Mar 26 at 5:43
• @user, I'm not sure how I am to tell which things you write are to be taken completely rigidly, and which allow room for exceptions. Maybe we could work out some signal, so in the future I'll be able to tell. – Gerry Myerson Mar 26 at 8:51
• @GerryMyerson: Usually, I try to be precise, using words like "typically" or "almost always" but, you know, that that is very tiring to do in every single statement. How about you just assume that there may be rare exceptions unmentioned unless I use the word "absolutely"? I don't think anyone is 100% precise all the time anyway, so that works for interpreting others' comments too. – user21820 Mar 26 at 8:59

Reopened

I would like to see this question opened:

Intersection of a nested sequence of subgroups

The OP has provided all the context requested in the comments. Also, it is an interesting and relatively hard question.

Undeleted, closed, deleted.

I nominate https://math.stackexchange.com/q/2991071/290189 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

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. – user334732 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. – user334732 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 :( – user334732 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. – user334732 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 – user334732 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! – user334732 Dec 3 '18 at 10:39

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. – T. Bongers Nov 27 '18 at 18:28

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

Undeleted, and deleted again

Please undelete https://math.stackexchange.com/q/3110919/290189 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

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

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.

unfortunately the question i asked https://math.stackexchange.com/questions/3056520/why-is-the-zero-polynomial-the-only-one-to-have-infinite-roots was put on hold as off-topic first then closed and then deleted . i edited it much for it to be reopened but it wasn't opened. i apologise if it was off- topic to you, but i edited it. If it being off topic yet, kindly suggest improvement or undelete it please.

• Have you finally made up your mind between "Wikipedia" and "wikipedia"? – Did Feb 3 at 21:37

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 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

## 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).