I cannot upgrade to MOJAVE.  After spending a lot of time searching through Apple's download site, I contacted Apple support and they told me that I cannot download Mojave 10.14.0.  That version has been removed from their download files.  Other later versions are still available.  However, I CANNOT INSTALL 10.14.4 OR 10.14.6 without first installing 10.14.0.  Are there any non Apple sites that make that 10.14.0 download available?????
Sometimes it's hard to search for older versions of macOS &amp; OS X  on the App Store.  This is an attempt to provide the canonical QA for this issue, as per the Meta QA -  I expect it to be modified over time to hopefully become a complete information resource.  How can I get any older version of a Mac OS to be able to run as a VM, or to reinstall on my Mac?
What does this notation mean? F|U If $F$ is a function and $U$ is a set, then what does $F|U$ mean?   In , the Inverse Function Theorem, the notation is used  Also, the file in stating the Lemma 2.14 states that $A \in U$, what does this mean? A set is an element of another set? What is $A$?  EDIT: Could someone kindly explain to me what is going on in Lemma 2.16. How does $\delta$ come into play? I dont see the role in the lemma. I also don't see why this proves one-to-one Makeindex error when ! used in \index in align environment See MWE below. The symbol ! in the \index causes an error. This is only the case in align environments (not in equation). So it seems to have to do something with amsmath. If ! is put in an \mbox there is no error. But then of course the font size is not adjusted to subindices. Curiously enough, \index{$C_{K!!}$} (two exclamation marks) doesn't cause any error.    \documentclass{article} \usepackage{amsmath} \usepackage{imakeidx} \makeindex \begin{document} \begin{align} y\index{$C_{K!}$} \end{align} \printindex \end{document}     Any solutions suggested? Proving or disproving inequality $ \frac{xy}{z} + \frac{yz}{x} + \frac{zx}{y} \ge x + y + z $ Fade in each element - one after another I am trying to find a way to load a JSON page to display my content, which I currently have. But I am trying to fade in each element one after another? Is anyone familiar with a way to do that?  Fade in each element with a slight delay?  Here is an example of my code, I am using the jquery framework.  CODE: Is there always an equivalent metric which is not complete? Can I combine extension tubes and macro filters at once to give better macros? This is Problem 6 of the 2007 Indian National Math Olympiad (INMO).  If $x, y, z$ are positive real numbers, prove that $(x+y+z)^2(yz+zx+xy)^2 \leq 3(y^2+yz+z^2)(z^2+zx+x^2)(x^2+xy+y^2).$  My best idea was to expand this and simplify. Although that doesn't look very feasible. Another idea is to see that $x^2+y^2+xy \geq x^2+y^2$. Then we just have to show that $(x+y+z)^2(yz+zx+xy)^2 \leq 3(x^2+y^2)(x^2+z^2)(y^2+z^2)$ if that is even true. I'm looking to download and install the latest version of Ubuntu to replace the current version of Windows I had pre-installed on my machine when bought it.   I have some really neat features on the machine that I really am hoping will still work when I move over to Ubuntu.  Can someone please confirm if the below will still work and, if not, how I can get them to work:   The USB ports on my machine The ethernet or Network work port on the machine The HDMI output on the machine and finally, the built in webcam   Thanks Sam How to add percent sign to NSString Inequality from Chapter 5 of the book *How to Think Like a Mathematician* This is from the book How to think like a Mathematician,  How can I prove the inequality $$\sqrt[\large 7]{7!} &lt; \sqrt[\large 8]{8!}$$  without complicated calculus? I tried and finally obtained just $$\frac 17 \cdot \ln(7!) &lt; \frac 18 \cdot \ln(8!)$$ How do I use SQL's GETDATE() and DATEADD() in a Linq to SQL expression? If I have a Linq to SQL expression like this:    from subscription in dbContext.Subscriptions  where subscription.Expires &gt; DateTime.Now select subscription   I want this to to use the SQL Servers GETDATE() function instead of the time of the machine running the C# program.  The next question would be how to translate this:  DateTime.Now.AddDays(2)   to this:  DATEADD(dd, 2, GETDATE()) Can I enter the Schengen area with a German long-term visa through a different country? I am an Indian national. Right now I am staying in Israel. I will be moving to Germany on the last week of this month with german national visa directly from tel aviv. Ticket price of direct flight is high. So I am thinking to buy either Air France or LOT for travelling having layover at Paris or Poland. Am I allowed to do that? I mean is it mandatory to enter in Germany first? May I travel with these airlines with proper transit visa? To an an external observer it appears that time has stopped for photon. But this relation is reflexive, so for an observer travelling with the photon it appears the universe has stopped everywhere.  Is this right?  Space also gets distorted parallel to the direction of motion, but not perpendicular to it.   Does this mean that for an observer travelling with a photon sees spacetime as a flat plane?  Note 1: I'm using language vividly not literally when I say a photon experiences space and time. Not that I'm against idealist or panpyschist interpretations of matter or energy come to that.  Note 2: Since it's been pointed out that an inertial frame can't be boosted into the frame of a photon and moreover there is no limiting behaviour here - no matter what frame you are boosted into, light will always appear to travel at c. Nevertheless, when an external observer watches a train chasing a photon by gradually increasing its speed, he will note that the train speed is approaching the speed of the photon (but will never match it) and when he looks at the clock inside the train he will not too that it is gradually slowing down (but never actually stops). Using this picture, we can attempt the thought experiment - if not one that can be carried out - of what a world looks like to a photon. Line-breaking widget layout for Android I'm trying to create an activity that presents some data to the user. The data is such that it can be divided into 'words', each being a widget, and sequence of 'words' would form the data ('sentence'?), the ViewGroup widget containing the words. As space required for all 'words' in a 'sentence' would exceed the available horizontal space on the display, I would like to wrap these 'sentences' as you would a normal piece of text.  The following code:  public class WrapTest extends Activity {     /** Called when the activity is first created. */     @Override     public void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         LinearLayout l = new LinearLayout(this);         LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(                 LinearLayout.LayoutParams.FILL_PARENT,                 LinearLayout.LayoutParams.WRAP_CONTENT);         LinearLayout.LayoutParams mlp = new LinearLayout.LayoutParams(                 new ViewGroup.MarginLayoutParams(                         LinearLayout.LayoutParams.WRAP_CONTENT,                         LinearLayout.LayoutParams.WRAP_CONTENT));         mlp.setMargins(0, 0, 2, 0);          for (int i = 0; i &lt; 10; i++) {             TextView t = new TextView(this);             t.setText("Hello");             t.setBackgroundColor(Color.RED);             t.setSingleLine(true);             l.addView(t, mlp);         }          setContentView(l, lp);     } }   yields something like the left picture, but I would want a layout presenting the same widgets like in the right one.        Is there such a layout or combination of layouts and parameters, or do I have to implement my own ViewGroup for this? Over 20GB of disk space is gone? System drive, OS is Windows 7 x64 SP1 Ultimate.    Windows Explorer shows 100GB of used space.  TreeSizeFree shows 75GB of used space.  Total Commander and FAR confirm TreeSizeFree's measurements (counting hidden files).  Shadow copy is using up to 5GB with the current usage of 1.36GB.  Running FAR from Win7 PE shows the same.  Checkdisk shows no bad sectors. Disk is an OCZ SSD.  SMART monitor suggests SSD condition is perfect.    Where is the rest of space gone? We are using Nginx to serve static files on a development platform. As it is a development platform, we'd like to disable caching so that each change is propagated to the server. The configuration of the VHost is quite simple:  server {   server_name  static.server.local;   root /var/www/static;    ## Default location   location / {     access_log        off;     expires           0;     add_header        Cache-Control private;   }  }   When we access an HTML file (http://static.server.local/test.html), we have no issue: the server returns a code 304 Not Modified as long as the file is not changed, and a 200 OK response with the modified file when the file is changed. However, it seems to behave differently with a Javascript or a CSS file. Once the file is changed, we get a 200 OK response as expected, but with the old text. Is there an internal cache mechanism in Nginx that could explain this behaviour? Or some configuration that we should add?    As a side note, here is the header returned by Nginx when the file has been modified (it seems correct):  Accept-Ranges:bytes Cache-Control:max-age=0 private Connection:keep-alive Content-Length:309 Content-Type:text/css Date:Fri, 13 May 2011 14:13:13 GMT Expires:Fri, 13 May 2011 14:13:13 GMT Last-Modified:Fri, 13 May 2011 14:13:05 GMT Server:nginx/0.8.54   Edit After trying different settings with the expires directive and Cache-Controlheader, I made some further investigations. In fact, the server is installed on a VirtualBox guest Ubuntu, and data are read from a shared folder that is on the Mac OSX host. If the file is edited from an IDE (NetBeans) on the host, it seems that changes do not appear whereas if I edit it directly on the guest (using VIM), it is refreshed. The strange thing is it does not behave similarly with HTML files. Quite puzzling.  Edit 2 (ANSWER) Indeed, the origin of the issue was more on the VirtualBox side. Or rather a conflict between VirtualBox and the "sendfile" option of the server. This link  gave me the solution: switch the sendfile flag in the server configuration to off:  sendfile  off;   Hope this could also help other person using VirtualBox for development. :) There are some additional information on the . Does $1^{\infty}=e$ or $1^{\infty}=1$? There are lots (an infinitude) of smooth functions that coincide with $f(n)=n!$ on the integers. Is there a simple reason why Euler's Gamma function $\Gamma (z) = \int_0^\infty t^{z-1} e^{-t} dt$ is the "best"?  In particular, I'm looking for reasons that I can explain to first-year calculus students. What really causes light/photons to appear slower in media? Game states & passing data between scenes