Lost keywords ranking with recent google Core web release?
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Is $D_n$, the dihedral group of order $2n$, isomorphic to a subgroup of $S_n$ ( symmetric group of $n$ letters) for all $n&gt;2$? How to find real world Selenium projects Where can I find sample or real Selenium projects. All the material I can find on github and on internet are basic, and never intermediate or advanced.  How does a real Selenium project look in real life? How can I find sample code? There are many different kind of options that you can do  in order to start using LaTeX on Ubuntu. I would prefer doing that through Eclipse, but if there is a better way of doing it, feel free to write your opinion on why using this instead of something else. How to change specific values in a List ,  and 1 still show the old bar. 1 See Arithmetic progression topology How did Groot manage to raise the axe of Thor when even Hulk failed? In Avengers Hulk tried to raise Thor's hammer and failed miserably. In Avengers: Infinity War, Groot raises Thor's new axe and holds it for a few seconds! Is the axe made of some other light material, or is Groot stronger than Hulk? Characterization of weak convergence in $\ell_\infty$ Is there some simple characterization of weak convergence of sequences in the space $\ell_\infty$? If yes, is there some similar claim for nets?   I was only able to come up with a characterization of sequential weak convergence using limit along ultrafilters, which I will describe below. I wonder whether there is some insight into this characterization. (E.g. whether there is some simple reformulations which does not use ultralimits.) Moreover, I do not know whether at least this characterization works for nets, too.  We have the following result describing weak convergence in $C(K)$, see e.g. Corollary 3.138,  in Banach Space Theory by Fabian, Habala et al. (It is a consequence of Rainwater theorem and characterization of extreme points of unit ball in $C(K)^*$.)     Let $K$ be a compact topological space. Let $\{f_n\}$ be a bounded sequence in $C(K)$ and $f\in C(K)$. Then, if $f_n\to f$ pointwise, we have $f_n\overset{w}\to f$.   Moreover we have isometric isomorphism between $\ell_\infty$ and $C(\beta\mathbb N)$, which is described e.g. in the Wikipedia article on  or in  of Carothers' book A short course on Banach space theory. This isomorphism assigns to each bounded sequence $(x_n)$ the continuous function $\overline x$ on $\beta\mathbb N$ defined by $$\overline x(\mathscr U) = \operatorname{\mathscr U-lim} x_n,$$ where $\operatorname{\mathscr U-lim} x_n$ denotes the  of $x_n$ w.r.t the ultrafilter $\mathscr U$.  Combining the above results we get the following characterization:      Let $f^{(n)},f\in\ell_\infty$. The sequence $f^{(n)}$ converges to $f$ weakly if and only if for every ultrafilter $\mathscr U$    $$\lim_{n\to\infty} \operatorname{\mathscr U-lim} f^{(n)}= \operatorname{\mathscr U-lim} f.$$   (The above claim for principal ultrafilters is just a pointwise convergence. But in the above claim the equality is required for free ultrafilters, too.) Flag apron shows superfluous closing anchor tag I awoke this morning to a spam flag on a site I moderate, and noticed this when I went to read the post.    Notice answered&lt;/a&gt;, which I imagine isn't meant to have the &lt;/a&gt; there.  I also confirmed that this displays asked&lt;/a&gt; for other types of flags (namely, closed without comment).   I looked around for a duplicate of this but can't seem to find it, so maybe it's a recent change? How can I link to an external resource in a community-friendly way? I would like to help my fellow Stackizens, using material from my blog or other website.  But external links are sometimes viewed as excessive promotion.  From the FAQ:     Be careful, because the community   frowns on overt self-promotion and   tends to vote it down and flag it as   spam. Post good, relevant answers, and   if they happen to be about your   product or website, so be it. However,   you must disclose your affiliation in   your answers. Also, if a huge   percentage of your posts include a   mention of your product or website,   you're probably here for the wrong   reasons.   I have tried posting answers that reference my blog, and I have followed the above rules, but my answers still get flagged as spam.  How can I craft an answer that references my blog, website or other resource, but is still acceptable to the community? Is there an unsubdivide function in Blender? I am wondering if there is a modifier or tool that will essentially undo a subsurf or subdivide command. Was Louis stalked days in advance too? Why did the Star Trek writers decide Warp 10 would be infinite? From  onward,  has a basically cubic scale from warps 1 - 9. But then, close to warp 10, it suddenly develops its own puzzling scale, as can be seen in .  In this scale, , occupying all points in the universe simultaneously and therefore effectively teleporting instantaneously.  My question is why have this confusing scale? Why not have a uniform cubic scale? Was there ever any "official" explanation for this?  Clarification: I'm looking for why the writers decided on this, not the "in-universe" explanation. I just started real analysis.  I don't have a background in proofs or logic, simply calculus.  So I'm trying to learn more about proofs--so forgive the basic question, please.  How do you go about proving this theorem: If $a$ and $b$ are any numbers, then there is one and only one number $x$ such that $a + x=b$.  This number is given by $x=b+(-a)$.  First part of the proof I understand--it's simple.  We simply use some axioms and do the following:  $a+b-a=b$, which of course is true.  This is just true from plugging in the $b+(-a)$ for $x$.  But how about the uniqueness issue?  In my text, it says:  $$(a+x)+(-a)=b+(-a) x=b+(-a)$$  How does this prove uniqueness?  Is this equation essentially saying that the ONLY possible value of $x$ is expressed by $b+(-a)$?  How would I have known to set this up as part of the proof if I was asked to prove something is unique?  Sorry for the basic question--have to start somewhere. How does quantization solve the ultraviolet catastrophe? Is the following layout possible with the subfigure package? The number of books in economics that we need to buy (is/are) three 1) The number of books in economics that we need to buy (is/are) three.   or       2) A number of books in economics that we can buy for the course (is/are) available in the college book store.   Possible answers:  a)is  b)are  My approach:  I am confused here why is and are are used in the 1 and 2 sentence.  What they exactly mean according to subject verb agreement rules. What cause the "from review" links to appear in comments? I sometimes see comments ending in "From Review" (hyperlinked to a review page) on questions and answers, e.g.        I spend a good bit of time in the review queues (on Unix &amp; Linux), but comments I make do not come with these "From Review" links. Note that I only have access to the "First post" and "Late answer" queues.  Do these links only appear for the higher-rep queues? Opening files from version 2.8 in 2.79 No secondary button (right click) on touchpad I'm experiencing a serious problem with the new Ubuntu 18.04:  System Dell XPS 13 with a freshly installed Ubuntu 18.04 LTS.  Problem description The touchpad provides only primary button (single click and double click), but no secondary button. In particular, when using the "test Your Settings" option in Settings -> Devices -> Mouse &amp; Touchpad, any click on the touchpad is signaled as primary button, no matter where I click (left or right side of the touchpad). This remains the case even after I change the Primary Button from Left to Right (in Settings -> Devices -> Mouse &amp; Touchpad -> General).  In comparison, an external mouse connected to my laptop (via usb) works fine: it provides both primary and secondary buttons with sides corresponding to the choice of Primary Button (in Settings -> Devices -> Mouse &amp; Touchpad -> General).  This may be related to   Any ideas?  Update: Meanwhile, I found out that in addition to the solution proposed by EntropyWins, one can also control this touchpad behavior via the Tweaks tool (a.k.a. gnome-tweaks) under Keyboard &amp; Mouse -> Touchpad -> Mouse Click Emulation. In any case, as EntropyWins explains in his answer, this is not a bug.