Integral form of $2\sum_{k=1}^{\infty}\frac{(2k-1)^2-1}{(2k-1)^4+(2k-1)^2+1}$
Find $\sum\limits_{k\, \text{ odd}} \frac{2(k^2-1)}{k^4+k^2+1}$
So I did a fresh install of Ubuntu 20.04 on a computer with the new RTL8125B Realtek network card and I cannot get the network to work. I was very suprised since this is supposed to be the new feature of the 5.4 kernel (I have 5.4.0-26-generic installed). Does anyone have any idea on how to get it working? Thank you. $ lspci -knn | grep Eth -A3 06:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8125 2.5GbE Controller [10ec:8125] (rev 04) Subsystem: ASUSTeK Computer Inc. RTL8125 2.5GbE Controller [1043:87d7] Kernel modules: r8169 07:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Ellesmere [Radeon RX 470/480/570/570X/580/580X/590] [1002:67df] (rev e7)  $ dmesg | grep -i r8169 [    0.911236] r8169 0000:06:00.0: unknown chip XID 641 how to pass value like 100,102,103 to view params I am trying to zoom plot numbers.Plot numbers like 1 10-12 13/P road 20(A) 100&amp;102 and etc.I am able to zoom to all combination plot numbers except 1,2,3.when I pass such value its trowing error:  1 feature types requested, but found 2 view params specified  geoserver sql view is:  select * from plotboundary where nmindar='%nmindar%' and plno='%plno%'   default values and validation are  Name  | Default Value   | validation  nmidar| Hanagawadi I A  | ^[\w\d\s]+$  plno  |  100,102&amp;103    | ^[ A-Za-z0-9_ *@.\/#&amp;+-\,()-_]*$   ajax function:   $.ajax({             url: 'http://XX.168.1.XX:8089/geoserver/XX/ows?service=WFS&amp;version=1.0.0&amp;request=GetFeature&amp;typeName=XX:vwplot&amp;maxFeatures=5000&amp;outputFormat=text/javascript',             contentType: 'application/json',             dataType: 'jsonp',             jsonpCallback: "parseResponse",             data: {                 viewparams: "nmindar:" + nmindar + ";plno:" + plno             }   Can any one tell me how to pass value to viewparams in geoserver, value includes comma. For example as mentioned above "100,102&amp;103" is a single value(plot number).Here   comma is not a separator. Set the default permission when creating a file How to solve and see resolution of $13^{53} \pmod 7$ using Fermat little Theorem? The particle number on my settings appear in gray, I don't think i'm able to change the number even thought i need it, how can i make it white again? Removing the first line of CSV file As an online shopper, I regularly use Amazon to purchase lots of stuff.  When I reconcile my credit card spending, I use Mail.app to search all mailboxes for specific dollar figures (e.g. command-option F, then type 24.95). Prior to Big Sur, finding dollar figures in Mail.app worked perfectly, whether the email messages resided &quot;On My Mac&quot; or on iCloud.  However, since Big Sur, doing a global Mail.app search for numeric strings, especially with a decimal point, doesn't work reliably. For example, I'll do a global search in Mail.app for 65.88 and I'll get one result from a locally archived message from years ago, however a very recent message in my InBox containing that figure is not found.  When I do a single message search (command-F) looking for 65.88, the value IS found. Unsurprisingly, using Spotlight delivers the exact same results. Using mdutil, I've manually erased and rebuilt the Spotlight index, rebuilt my Mail.app mailboxes, deleted all ~/Library/Mail/V8/MailData/Envelope* files to force the Mail.app to re-import everything, and reinstalled Big Sur.  I've also confirmed all my Spotlight settings to assure that Mail and Messages are included in searches, and that the volume where my mail resides is not excluded.  Nothing worked. I should note that I am using one SSD for macOS, and a separate SSD for my Home directory (c/o &quot;Advanced Options&quot; under Users &amp; Groups).  I've had this setup well before Big Sur, again, without any issues. Interestingly, I tried using the Spark email app, which DID successfully find dollar figures without any issue.  I suspect that Spark is not relying on Spotlight to obtain search results, and that's why it works.  (I would use Spark, however it doesn't support local mailboxes.) I've already sent Apple a report using the Feedback Assistant, and I can only hope something will get fixed. Can anyone else confirm this issue with Mail.app on Big Sur?  Any ideas on what else I can do? I love R. Courant and F. John's Introduction to Calculus and Analysis because of its wide coverage, precise description and friendly written style.  Are there any classic textbooks like it on ODE/PDE?  thanks. What is a race condition? When writing multithreaded applications, one of the most common problems experienced is race conditions.    My questions to the community are:  What is the race condition? How do you detect them? How do you handle them? Finally, how do you prevent them from occurring? My script (should) acts differently, depending on the presence of the data in the input stream. So I can invoke it like this:  $ my-script.sh   or:  $ my-script.sh &lt;&lt;-MARK     Data comes...     ...data goes. MARK   or:  $ some-command | my-script.sh   where two last cases should read the data, while first case should notice the data is missing and act accordingly.  The crucial part (excerpt) of the script is:  #!/bin/bash local myData; read -d '' -t 0 myData;  [ -z "${myData}" ] &amp;&amp; {     # Notice the lack of the data. } || {     # Process the data. }   I use read to read input data, then option -d '' to read multiple lines, as this is expected, and the -t 0 to set timeout to zero. Why the timeout? According to  (typing left unchanged; bold is mine):     -t timeout time out and return failure if a complete line of input is               not read withint TIMEOUT seconds.  The value of the TMOUT               variable is the default timeout.  TIMEOUT may be a               fractional number.  If TIMEOUT is 0, read returns success only               if input is available on the specified file descriptor.  The               exit status is greater than 128 if the timeout is exceeded   So I in case 2 and 3 it should read the data immediately, as I understand it. Unfortunately it doesn't. As -t can take fractional values (according to above man page), changing read line to:  read -d '' -t 0.01 myData;   actually reads the data when data is present and skips it (after 10ms timeout) if it is not. But it should also work when TIMEOUT is set to real 0.  Why it actually doesn't? How can this be fixed? And is there, perhaps, alternative solution to the problem of "act differently depending on the presence of the data"?  UPDATE  Thanks to @Isaac I found a misleading discrepancy between quoted on-line version and my local one (normally I do not have locale set to en_US, so help read gave me translation which I couldn't paste here, and looking up for on-line translation was faster than setting new env---but that caused the whole problem).  So for 4.4.12 version of Bash it says:     If TIMEOUT is 0, read returns               immediately, without trying to read any data, returning               success only if input is available on the specified               file descriptor.   This gives a little bit different impression than "If TIMEOUT is 0, read returns success only if input is available on the specified file descriptor"---for me it implied actually an attempt to read the data.  So finally I tested this and it worked perfectly:  read -t 0 &amp;&amp; read -d '' myData;   The meaning: see if there's anything to read and if it succeed, just read it.  So as to base question, the correct answer was provided by Isaac. And as to alternative solution I prefer the above "read &amp;&amp; read" method. How to sum a variable by group Can someone give me an example of a function $f: I\to \mathbb R$ which is uniform continuous but not Hölder continuous (for any $\alpha$)? Here $I$ is an interval. If $I$ is closed and bounded then we are essentially assuming that $f$ is merely continuous.   By saying that $f$ is not Hölder continuous for any $\alpha$, I mean for all $\alpha &gt;0$,   $$\sup_{x,y\in I, x\neq y} \frac{|f(x) - f(y)|}{|x-y|^\alpha} = \infty.$$  That is, I need to find a function $f$ so that for all $\alpha$ and $M&gt;0$, there are $x, y\in I$ so that   $$ \frac{|f(x) - f(y)|}{|x-y|^\alpha} \ge M.$$  I know that $f(x) = x^\alpha$ are $\alpha$-Hölder continuous. Thus, in some sense, I am looking for $f$ which are worst than the functions $x^\alpha$ for all $\alpha &gt;0$. What happens to the temperature when an ideal gas is compressed? I am rather confused about this. I know from Charles' law that under constant pressure, the volume of a gas is directly proportional to its absolute temperature i.e.  $$\frac{V_1}{T_1} = \frac{V_2}{T_2}$$  Thus accordingly, during compression, temperature of the gas would decrease. But in Lectures of physics ,vol 1 by Feynman, it is written:     Suppose that the piston moves inward, so that the atoms are slowly compressed into a smaller space. What happens when an atom hits the moving piston? Evidently it picks up speed from the collision. [...] So the atoms are "hotter" when they come away from the piston than they were before they struck it. Therefore all the atoms which are in the vessel will have picked up speed. This means that when we compress a gas slowly, the temperature of the gas increases.   (Constant pressure?) So, this is contrary to Charles' law. Why does this happen? Who is right? Or are they both correct? I am confused. Help. How do you list the primary key of a SQL Server table? When to use Stateful session bean over Stateless session bean? I am pretty sure $(B_{t}^{2})$ not Markov because the squared random walk is not.    I guess I can repeat the method since to be Markov it must satisfy the discrete.  Thanks How to fairly select a random number for a game without trusting a third party? Where can I find historical data on arrival and departure times of a particular flight? Where can I find historical data on flights, specifically Delta international flights?  I need to find out about cancellations, diversions and any other flight data pertaining on particular route at a given time.  This source has to be official and stand up to legal scrutiny. What are review tests (audits) and how do they work? I recently received this rather amusing message while reviewing a user's first post:  Congratulations! This was only a test, designed to make sure you were paying attention. This post has already been removed, but thanks for taking time to leave feedback for the author.   What is the purpose of this test? How does the audit work? What happens if I fail? Why was the system expecting me to negatively review a good post, or positively review a bad post? A review is obviously an audit. Should I report it? Do review audits count toward the Reviewer badge? Do robo-reviewers dream of electric sheep? I am Peruvian, and will study in the Turkish Republic of Northern Cyprus for two years.  As a South American, what problems may I have if I decide to study in the TRNC, as it is recognized only by Turkey?  What if, having been in the TRNC, I decide to travel to the EU (Amsterdam) for summer vacations? Would I encounter any problem entering The Netherlands, a member of EU, after having been in the TRNC?  I have read that many tourists (Russians and Asians for now) are deported mostly because they go from Northern Cyprus to the Republic of Cyprus. Cyprus, a member of the EU, believes that those entering the country from the north are illegal immigrants. Does this rule apply to Cypriot internal issues only, or does it extend throughout the EU? Will it cause problems for my intended travel to Amsterdam?