Limit of a product sequence for infinite terms
Evaluating the infinite product $\prod\limits_{k=2}^\infty \left ( 1-\frac1{k^2}\right)$
The website I'm working is allegedly going to have a massive hit rate soon after launch. The client is talking about the possibility  of around 2500 hits per second over a day or so.   Ignoring the fact that this hit rate is probably wild client optimism and apart from getting the largest servers possible, what is the best way that Drupal should be configured to support a large hit rate.  I've read Scaling the , ,  and many other pages, but what I'm looking for is real experience of doing this, what works, what doesn't, and what to expect. Allow retracting a moderator flag if the post has been deleted and I don't have enough reputation to see deleted posts Currently, custom flags for moderator attention are not automatically invalidated (marked helpful) when a post gets deleted. Ordinarily, one can retract a moderator flag by going to the post, clicking &quot;flag&quot;, and then &quot;Retract Flag&quot;. This works even if the post has been deleted, provided they can see the post (they have 10,000+ rep, it's their own post, or they have answered it). However, it's not possible to self-remove a flag on a deleted post if they can't see the deleted post, because they can't get to the &quot;flag&quot; button. Is this intended? If not, can this ability please be implemented? As Aurora0001 commented, there is no server-side check, the button is just not visible. Can this please be implemented on the website, or is the fact that it's possible server-side a bug that will soon be fixed by removing it? Why GCP Kubernetes Node host location for europe-north1 seems to be in US? I am new to both Google Cloud Platform and K8s. I have launched Kubernetes cluster in GCP and chosen europe-north1 as the region (europe-north1-a as the zone).   When I try to run my application on this cluster it fails because it expects the application to run in EU region. I added IP and Geo check (using GeoLite database () and AWS IP check tool ()) into my application and they tell me that the host is located in US.  Have I perhaps missed some GCP/K8s configuration option or is this because the europe-north1 region is still quite new and the IP addresses do not correctly show that they are located in EU? In which case I should direct this question to Google? Is it possible to download using the Windows command line? Without using any non-standard (Windows included) utilities, is it possible to download using the Windows command line?  The preferred version is Windows XP, but it's also interesting to know for newer versions.  To further clarify my question:   It has to be using HTTP The file needs to be saved Standard clean Windows install, no extra tools   So basically, since everybody is screaming , I want simple Wget functionality, without using Wget. What kind of things can you take from a hotel? Hotels normally provide a big amount of sets (well, depending on the quality, but however, many!) that can help you feel more comfortable there.  So for example you can get towels, slippers, candies, pens, shampoos, shaving kits, sponges, ...  The same in the self-service breakfast: pastries, bread, ...  They are meant to be used during your stay. However, they can be provided in such an amount that there are some extra by the time you leave... and make you feel like taking some back home.  My general rule is to take those things that I used but didn't finish. However, sometimes I may be tempted to take the brand new stuff lying there before I close the door for the last time.  So the question that pops is: what kind of things is it correct to take from hotels and what is it not recommended? Else, what items may differ from country to country? How can I backup my RAW photos while travelling without Internet access? Software gvSIG OA Digital Edition 2010 have tools topology for finding pseudo nodes in linear geometry. I set cluster tolerance 0.00002 and maximum number of errors -10000 for 20000 link count linear geometry. But unsuccessful result.   Are there any solutions that find pseudo nodes in free GIS software?   I need to layer pseudo nodes (one solution to this problem - to use tools topology of ArcInfo, but priority for me is to use free software). Linear geometry created several users in QGIS 1.8.0 in PostGIS (v. 2.0.1) database.  Add new image: 12 linear features with three pseudo nodes in A (line 4/5), B (line 6/7), C (line 9/10). Pseudo nodes should be points instead - two linear features with intersection in one point (node) should be one linear feature (line 4/5 - line 4, ...).  Is it possible to make a request in PostGIS, which will result in a layer of pseudo nodes?  Add new image of examples pseudo nodes: if I receive for linear layer point layer pseudo nodes (blue rects) I corrected following errors in linear layer: A - add missing geometry, B - snapped line in intersection, C - remove pseudo node. Where can I find the status of the released versions of Ubuntu? I want to know where I can find updated information about all the stable and in-development versions of Ubuntu, where I can find this information?     This question is meant to be a canonical question. It expects to answer the following questions:         Is X version stable yet?   Is X version in beta?   Is X version still supported?   What versions are still supported?   What are the versions in Beta/Alpha?   Until where X version will be supported?   Have X version ceased support?   When will be X version released?   Where I can download any release?   When will the next LTS version of Ubuntu be released?         The list is not exhaustive. This is a  about Hosting multiple SSL websites on the same IP.   I was under the impression that each SSL Certificate required it's own unique IP Address/Port combination. But the  is at odds with this claim.  Using information from that Question, I was able to get multiple SSL certificates to work on the same IP address and on port 443. I am very confused as to why this works given the assumption above and reinforced by others that each SSL domain website on the same server requires its own IP/Port.  I am suspicious that I did something wrong.  Can multiple SSL Certificates be used this way? "Do you want to continue[Y/n]?" Why the upper case? I am new to Ubuntu and some little thing start to bug me. Such as when trying to install a program, Ubuntu asks,     Do you want to continue[Y/n]?   What is bugging me is why the letter "Y" is upper case and "n" is lower case. Do they have any significant reason why one is upper and the latter is lower? Whatever case I enter it doesn't change the outcome: it either continues or not. Are they trying to notify us that we can enter both and it won't change anything? Err http://archive.canonical.com natty InRelease     Err http://security.ubuntu.com oneiric-security InRelease                Err http://extras.ubuntu.com natty InRelease                             Err http://security.ubuntu.com oneiric-security Release.gpg   Temporary failure resolving ‘security.ubuntu.com’ Err http://archive.canonical.com natty Release.gpg   Temporary failure resolving ‘archive.canonical.com’ Err http://extras.ubuntu.com natty Release.gpg   Temporary failure resolving ‘extras.ubuntu.com’ Err http://gb.archive.ubuntu.com oneiric InRelease Err http://gb.archive.ubuntu.com oneiric-updates InRelease Err http://gb.archive.ubuntu.com natty-backports InRelease Err http://gb.archive.ubuntu.com oneiric Release.gpg   Temporary failure resolving ‘gb.archive.ubuntu.com’ Err http://gb.archive.ubuntu.com oneiric-updates Release.gpg   Temporary failure resolving ‘gb.archive.ubuntu.com’ Err http://gb.archive.ubuntu.com natty-backports Release.gpg   Temporary failure resolving ‘gb.archive.ubuntu.com’  Reading package lists... Done W: Failed to fetch http://gb.archive.ubuntu.com/ubuntu/dists/oneiric/InRelease       W: Failed to fetch http://gb.archive.ubuntu.com/ubuntu/dists/oneiric-updates/InRelease   W: Failed to fetch http://gb.archive.ubuntu.com/ubuntu/dists/natty-backports/InRelease   W: Failed to fetch http://security.ubuntu.com/ubuntu/dists/oneiric-security/InRelease   W: Failed to fetch http://archive.canonical.com/ubuntu/dists/natty/InRelease   W: Failed to fetch http://extras.ubuntu.com/ubuntu/dists/natty/InRelease   W: Failed to fetch http://archive.canonical.com/ubuntu/dists/natty/Release.gpg  Temporary failure resolving ‘archive.canonical.com’ W: Failed to fetch http://security.ubuntu.com/ubuntu/dists/oneiric-security/Release.gpg  Temporary failure resolving ‘security.ubuntu.com’ W: Failed to fetch http://extras.ubuntu.com/ubuntu/dists/natty/Release.gpg  Temporary failure resolving ‘extras.ubuntu.com’ W: Failed to fetch http://gb.archive.ubuntu.com/ubuntu/dists/oneiric/Release.gpg  Temporary failure resolving ‘gb.archive.ubuntu.com’ W: Failed to fetch http://gb.archive.ubuntu.com/ubuntu/dists/oneiric-updates/Release.gpg  Temporary failure resolving ‘gb.archive.ubuntu.com’ W: Failed to fetch http://gb.archive.ubuntu.com/ubuntu/dists/natty-backports/Release.gpg  Temporary failure resolving ‘gb.archive.ubuntu.com’ W: Some index files failed to download. They have been ignored, or old ones used instead.   This is what I'm seeing when I try to run sudo apt-get update. I did an update on my instance yesterday and am now experiencing this. Average distance between two random points in a square How to make a modification take affect without restarting nginx? Apache has a graceful option which can scan for modification in http.conf without restarting Apache. What about nginx? Prove $\gcd(a+b,a^2+b^2)$ is $1$ or $2$ if $\gcd(a,b) = 1$ Assuming that $\gcd(a,b) = 1$, prove that $\gcd(a+b,a^2+b^2) = 1$ or $2$.   I tried this problem and ended up with $$d\mid 2a^2,\quad d\mid 2b^2$$ where $d = \gcd(a+b,a^2+b^2)$, but then I am stuck; by these two conclusions how can I conclude $d=1$ or $2$?  And also is there any other way of proving this result? I realize this is a long shot, but my phone was lost or stolen a few hours ago.  At the time it was stolen, I didn't have any specific applications installed to track it or wipe the data. So... my bad. I'm hoping the fact that I have a pattern lock will at least prevent anyone from accessing my data.  My question is, do I have any options for tracking or data wipe after the fact? (I'm more interested in tracking.)  Note: I have read similar questions, but unless I'm mistaken, they all address the question in terms of preparation before losing the phone. I'm asking about fallback options after losing the phone. I would like to read in a number of files and pipe their output to subsequent programs while still maintaining them as individual pipelines of data.  program1 *.txt | program2 | program3 folder   I know what the above syntax can accomplish for single streams of data, but I am looking at keeping the files separate throughout the entire operation. The above would translate to the following:   program1 reads text files and pipes to program2 program2 processes data individually and pipes to program3 program3 writes data to files in folder with the same file names as the original   This kind of operation is currently the domain for build tools like Gulp, but I am trying to see if a shell can fully replace them. Since programs are written to handle only one stdin, it doesn't seem feasible.  The reading and writing of multiple files isn't an issue as I will just handle that within the programs themselves.  I have looked into the following, but they don't seem like the correct solution:   the tee command file descriptors substitutions   One possible way is to create a process for each individual file, and maintain a list of file names somewhere, but I am hoping for something more elegant. I had originally coded the program wrongly. Instead of returning the Fibonacci numbers between a range (ie. startNumber 1, endNumber 20 should = only those numbers between 1 &amp; 20), I have written for the program to display all Fibonacci numbers between a range (ie. startNumber 1, endNumber 20 displays = First 20 Fibonacci numbers). I thought I had a sure-fire code. I also do not see why this is happening.  startNumber = int(raw_input("Enter the start number here ")) endNumber = int(raw_input("Enter the end number here "))  def fib(n):     if n &lt; 2:         return n     return fib(n-2) + fib(n-1)  print map(fib, range(startNumber, endNumber))   Someone pointed out in my Part II (which was closed for being a duplicate - ) that I need to pass the startNumber and endNumber through a generator using a while loop. Can someone please point me in the direction on how to do this? Any help is welcome.    I'm a learning programmer and I've run into a bit of a jumble. I am asked to write a program that will compute and display Fibonacci's Sequence by a user inputted start number and end number (ie. startNumber = 20 endNumber = 100 and it will display only the numbers between that range). The trick is to use it inclusively (which I do not know how to do in Python? - I'm assuming this means to use an inclusive range?).  What I have so far is no actual coding but rather:   Write Fib sequence formula to infinite Display startNumber to endNumber only from Fib sequence.   I have no idea where to start and I am asking for ideas or insight into how to write this. I also have tried to write the Fib sequence forumla but I get lost on that as well. What is the "canary thread" and why is it starving? I've come across some strange interaction between overlay specification and \pause. Basically I have an itemize and after some text(or block). I want to step through the itemize and after that show the text/block.  I've tried to put a simple \pause between the itemize and the text, but in this way two slides are created, both with the full itemize and no text.  If I don't put the \pause the text is visible from the start(which I don't want).  I've already found a simple work-around: instead of using itemize[&lt;+-&gt;] I can specify the slides on the items(e.g item&lt;1-&gt;, ...item&lt;2-&gt;,... \pause), but I don't like this solution for some reasons:   I have to type more than before I have to hard-code the slide numbers This is solution is not robust. Modification on the item order, removal or addition of new items would break it. I think there has to be some better solution.   So, how should I do?  By the way, a minimal example:  \documentclass{beamer}  \usepackage[utf8]{inputenc} \usepackage{default}  \begin{document}  \begin{frame}     \begin{itemize}[&lt;+-&gt;]         \item A         \item B         \item C     \end{itemize}      \pause  % double pause here      Some text. \end{frame}  \end{document} I can't work out why Altium is doing this, or how to undo it, or how to make it stop doing it.  It happens when I use the 'Find Similar Objects... ' option; all of objects that it hasn't found are faded out and I can no longer select them.  Anyone know how to fix this?  Additionally, if anyone knows how to change, en masse, the components' footprint library to 'Any' through the SCH inspector, that'd be really helpful too.