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Jul 19, 2023 14:42

-2

I came up with a proof that I think holds up to prove that the Collatz Conjecture will always result in the 4,2,1 loop. If anyone could take a look at it and let me know how to improve it, that would be great! The basis for the proof comes from the idea that 3x+1 will only produce even powers of ...

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Nov 28, 2021 05:30

1

Q: Is it possible to improve on these bounds for $\frac{\varphi(n)}{n}$, if $q^k n^2$ is an odd perfect number with special prime $q$?

Let $N = q^k n^2$ be an odd perfect number with special/Eulerian prime $q$ satisfying $q \equiv k \equiv 1 \pmod 4$ and $\gcd(q,n)=1$. Denote the Euler-totient function of the positive integer $x$ by $\varphi(x)$, and the classical sum of divisors of $x$ by $\sigma(x)=\sigma_1(x)$. MOTIVATION Fr...

number-theory upper-lower-bounds totient-function divisor-sum perfect-numbers

Xander Henderson

Nov 20, 2021 17:29

cv-pls fractions Is this of any use? Looking for exercises to improve mental math with decimals, specifically multiplication and division.‭ - Thomas Hegarty‭ 2021-11-20 16:19:36Z

Xander Henderson

Dec 19, 2019 18:16

@user21820 I'm a little torn on D8; I'm not sure what additional context the asker could provide which would improve the question, and it seems like a reasonable question for the puzzle tag. On the other hand, it is a pretty bare question. My inclination is to leave it close, but not deleted. That being said, I don't have strong emotions in either direction.

Martin Sleziak

Dec 15, 2019 07:34

titles improve I have edited the title to remove \dfrac (which is recommended against): How do I show that $\frac{\exp(yz)}{\sum_{y'=0}^1\exp(y'z)} =\sigma((2y-1)z)$? Would it be better to write there something like "$\exp(yz)/\left(\sum_{y'=0}^1\exp(y'z)\right)$"? (Maybe add _\limits to the sum?)

Xander Henderson

Nov 18, 2019 15:48

del-pls calculus The asker has had two days to improve the question and provide the context I (and others) asked for. They have not. Summing $\sum_{k=0}^\infty q^{2k}$ and $\sum_{k=0}^\infty q^{2k+1}$‭ - TKN‭ 2019-11-15 22:46:51Z

Xander Henderson

Aug 19, 2019 22:08

The title was originally something about "analytical analysis" and the question was tagged real-analysis. I have tried to improve the title and tagging, but would welcome further input from others.

Martin Sleziak

Jun 3, 2019 07:50

improve I have also tried to edit Minimize $a+b+c+d$ given $\text{LCM}(a,b,c,d)=1000$ - this question cause some heated debate recently. I wonder whether the version after my edit would already be considered as having sufficient context.

Martin Sleziak

Jun 3, 2019 07:44

improve Is the sum of singular and nonsingular matrix always a nonsingular matrix? (from reopen request thread). This seems like a question which is natural to ask, so it might be useful to have some counterexamples here on site.

Martin Sleziak

Jan 22, 2019 15:45

@user1729 improve If the question is being edited to a better form, perhaps adding link to the question showing that different order of three elements lead to the same order might by suitable addition: Let $G$ be a group. Show that $\forall a, b, c \in G$, the elements $abc, bca, cab$ have the same order..

TheSimpliFire

Jan 7, 2019 20:04

102

Q: How can we stop premature deletion?

Update: discussion on specific changes to how deletion works is here: Turbocharging the Roomba: solutions for premature deletion This needs to stop: https://stackoverflow.com/posts/15348333/revisions It doesn't help to improve close descriptions or encourage fixing and reopening if clo...

discussion deleted-questions vote-to-delete

Xander Henderson

Dec 24, 2018 18:37

close This asker has had quite a bit of time to improve their question, but has not done so.

Martin Sleziak

Mar 7, 2018 02:31

improve I have tried to edit 2665553: Calculating the summation$\sum_{n=1}^{\infty}\frac{H_{n+1}}{n(n+1)}$. Further improvements are more than welcome.

Martin Sleziak

Feb 23, 2018 05:04

It is easy to search for such messages: undelete, reopen, re-open, improve.

Martin Sleziak

Feb 19, 2018 12:22

improve Since this questions was brought up anyway: Is there a $2 \times 2$ real matrix $A$ such that $A^2=-4I$? What would be a good way to improve this question - so that it no longer is missing context.

Martin Sleziak

Oct 25, 2017 13:26

duplicates improve It seems that there are several questions about the fact that $A^2=I$ implies that sume of ranks of $A+I$ and $A-I$ is $n$. (I will post the one I found below.) It would be nice to choose the best duplicate target (and, if needed, improve it so that it is not closed for lack of context.)

Martin Sleziak

Sep 11, 2017 05:17

@user21820 improve Does somebody have suggestions how Calculate $\frac{1}{\sin(x)} +\frac{1}{\cos(x)}$ if $\sin(x)+\cos(x)=\frac{7}{5}$ could be improved to have sufficient context (so that it could stay on the site)? I did my best to include something reasonable in my recent edit, but I would be grateful for suggestions for further improvements.

Martin Sleziak

Aug 31, 2017 04:56

@SimplyBeautifulArt reopen improve I have edited the question How to solve such a quadratic question: If $a^2 -a -3=0 $ then $a^3$ equals $a+1$, $2a+1$, $4a+1$, $4a+3$ or $5a+3$ (revisions/timeline) and added description of OPs own attempts mentioned in the comments.

Martin Sleziak

Aug 25, 2017 06:48

improve Is $\sum_{n=1}^\infty \frac{1}{2^{n^2}}$ is rational number? - this seems to be a similar case.

Martin Sleziak

Aug 20, 2017 13:07

Aug 12 at 7:49, by Martin Sleziak

delete or improve This answer has some delete votes: [Definite integral $\int_2^{343} ({x-[x]})^2 dx $](https://math.stackexchange.com/q/2388824#2390823). I have at least edited WA links into the post, perhaps some further improvements can be done...?

Martin Sleziak

Aug 17, 2017 10:08

improve As I mentioned before, I find answers to this question quite useful: How can we factorize $x^4 - 2x^2 + 49$ with coefficients in $\mathbb{R}$? So I'd prefer if the question stays for the sake of the answers. I have already edited the post. Any suggestions for further improvements?

Martin Sleziak

Aug 12, 2017 07:49

delete or improve This answer has some delete votes: [Definite integral $\int_2^{343} ({x-[x]})^2 dx $](math.stackexchange.com/q/2388824#2390823). I have at least edited WA links into the post, perhaps some further improvements can be done...?

Martin Sleziak

Jul 31, 2017 12:33

deletion improve 2358652: Prove $\log _{81}x+\log _x3\ge 1$ - timeline/revisions. This does not seem a very good question - nothing beyond the statement of them problem. Should it be deleted? Or is there some relatively easy way to edit it into a better shape?

Martin Sleziak

Feb 5, 2017 09:44

improve This title seem to have quite big vertical height.

Martin Sleziak

Jan 8, 2017 08:27

improve Several users put some effort into answer to How can we factorize $x^4 - 2x^2 + 49$ with coefficients in $\mathbb{R}$? It has one delete vote, perhaps it might be good to improve the post a bit to increase the chance that the answers are preserved.

Martin Sleziak

Dec 6, 2016 05:26

improve Any ideas how to make title of this question better (more descriptive)?

Martin Sleziak

Nov 30, 2016 05:25

improve The question Proving prime $p$ divides $\binom{p}{k}$ for $k\in\{1,\ldots,p-1\}$ is closed as off-topic while several other questions are closed as duplicates of this question.

Martin Sleziak

Aug 14, 2016 11:16

@quid I agree that it would be ideal to have an input from some of the users active in integration tag. Perhaps you could add a comment on the question. Additionally the tags indefinite-integrals and maybe also trigonometric-functions should be added to the question. That would bump it - and improve the chances that there will be some feedback on your comment.

Martin Sleziak

Aug 8, 2016 06:25

Do you think that it is possible that post that have some minor flaws (incorrect tagging, typos, picture instead of MathJax) or posts which get into review queues do get more views (more attention) simply because other users try to edit and improve them, which causes bumping?

Najib Idrissi

Sep 29, 2015 14:33

This question is missing context (and closed at such); but it is the most frequently linked question in the indefinite-integral tag, and it has good answers. Does anyone have an idea for how to improve it so that it's not missing context anymore?

Martin Sleziak

May 28, 2015 10:13

improve Finding solutions of a system of linear equations

Martin Sleziak

Feb 10, 2015 07:26

improve I have added at least one sentence to Evaluate the integrals $\int \sin{x} \cot^2{x} \,dx$ and $\int \cos{x} \cot^2{x} \,dx$.. The question was put on hold as missing context and other details.

Martin Sleziak

Apr 6, 2014 09:07

9

Q: What is the term for a factorial type operation, but with summation instead of products?

(Pardon if this seems a bit beginner, this is my first post in math - trying to improve my knowledge while tackling Project Euler problems) I'm aware of Sigma notation, but is there a function/name for e.g. $$ 4 + 3 + 2 + 1 \longrightarrow 10 ,$$ similar to $$4! = 4 \cdot 3 \cdot 2 \cdot 1 ,$$...

algebra-precalculus terminology faq

Martin Sleziak

Nov 21, 2013 11:26

3

Q: Preview of a proposed edit?

Is there a way, when reviewing a proposed edit, to preview it exactly as the edited text would appear on the site? I used the "improve" option for this purpose a couple of times but then I got insulted that I failed the idiot test since what was I thinking trying to improve an already rejected e...

support review review-audit

Martin Sleziak

Nov 21, 2013 11:26

31

Q: Audits: this is getting ridiculous.

I was looking at the suggested edits list. There was this question where I couldn't make sense of the edits that were shown to me. So I click on "improve" to see the question properly, as the formatting in the queue is not particularly appealing. And then I get the "you failed an audit; you didn'...

discussion suggested-edits review-audit