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Beamer: PDF presentation viewer to play embedded videos and show elapsed time I have been suffering from finding a PDF presentation viewer for beamer output on Windows that can play embedded videos (by media9 package) and show the elapsed presentation time. I have tried the following: Adobe Reader with tdclock package:  Pros: plays videos and loads tdclock properly Cons: sluggish and crashes frequently  Foxit Reader with tdclock package:  Pros: smooth viewer and plays videos  Cons: can't load tdclock clock/stopwatch despite enabling javascript   Impressive:  Pros: fast and has internal clock  Cons: can't play embedded videos   Dual-Screen PDF Viewer:  Pros: very fast, has internal clock and dual screen support  Cons: can't play embedded videos   Is there any other solution that can properly play embedded videos and show elapsed presentation time flawlessly and smoothly on Windows?  P.S. when I mean tdclock javascript is not loaded, those empty red boxes show up instead of the clock/stopwatch,  and when embedded video can't be loaded, a white page shows up. Homeomorphism that maps given points to given points when is f@g not the same as f[g]? How to run an executable on boot and keep it running? I have an executable build from a ndk-build program. I want to run it on a rooted Android device. How much is the possibility that Android will kill my executable?  Using adb shell, I am able to execute my executable using following commands:  adb push executable /sdcard adb shell device:/ $ su device:/ # cd /system device:/system # mount -o rw,remount /system device:/system # mv /sdcard/executable . device:/system # ./executable   My requirement is to run this executable on device boot.  I have tried following:   Write ./executable in init.rc.   On reboot init.rc reset to its original contents. I figured out that Magisk done this.  Write commands in /system/etc/init/bootstat.rc   ./executable service custom /system/executable on boot  ./system/dhandler/diag_revealer    None of the above thing is working. I came to this conclusion: the primes that can't be written as the sum of two squares (lets use$p\prime$ to denote) can be written as ${p}\prime \equiv 3 \;(\bmod\; 4)$.  I need a simple proof to show this and am stuck. I would appreciate guidance! Close Vote Review, additionally filter off-topic close reasons Explicit bijection between the successor of $\alpha$ and $\alpha$ (infinite ordinal). I would like to construct an explicit bijection from $\alpha^*$ to $\alpha$, where $\alpha$ is an infinite ordinal. I have been told a possible bijection would be:  \begin{equation} f(\beta) = \begin{cases} 0 &amp; \text{if } \beta = \alpha \\ \beta^* &amp; \text{if } \beta \text{ is finite} \\ \beta &amp; \text{otherwise} \end{cases} \end{equation}  I don't understand how this is constructed, or why it is a bijection. I am a software engineer but try to keep up with maths as I really enjoyed the subject at school. I just saw a great TED talk:   The talk states that the current largest known prime is $2^{57885161}-1$  This got me thinking - how does one actually prove whether a number this large is prime or not?  Is it just done by brute force via a computer algorithm or are there any well known mathematical techniques for doing so?  I would be really grateful for any pointers as I am eager to learn about these techniques (if they exist). How to obtain and use the .bbl file in my tex document for ArXiv submission? I am submitting my first article to ArXiv and in the instructions they specify I have to include the .bbl file. Their instructions are:  "We do not run BibTeX in the auto-TeXing procedure. If you use it, include in your submission the .bbl file that BibTeX produces on your own machine; otherwise your references will not come out correctly. We do not run BibTeX because the .bib database files can be quite large, and the only thing necessary to resolve the references for a given paper is the .bbl file. The name of the .bbl file must match the name of the main .tex file for the system to process the references correctly."  My knowledge of LaTeX is basic, and I have not heard of .bbl file before. I am using TeXmaker. I have my tex file and my bib file. So what do I exactly do to obtain the .bbf file correctly and submit the article?  Thanks a lot! I am a Physics undergrad, and just started studying Topology. How do you define neighborhood and open set in Topology.Wikipedia gives a circular definition.   An  is defined as follows.      In topology, a set  is called an open set if it is a neighborhood of every point    While a  is defined as follows:     If $X$ is a topological space and $p$ is a point in $X$, a neighbourhood of $p$ is a subset $V$ of $X$, which includes an open set $U$ containing $p$   which itself contains the term open set.  How do you define it exactly? For what values of $\alpha$, does this integral converge? For what values of $\alpha&gt;0$ this integral converges $$\int_0^{\infty} \frac {\sin x}{x^{\alpha}}dx $$ Which site deals with career development questions for programmers? Is there any site in the network where career development questions about the programming profession can be asked ? I thought Programmer's was the site for it, but that doesn't appear to be the case. I'm creating a beamer presentation, in which I use TikZ.  I am making a figure, on which I would like to highlight something (using \only&lt;&gt; command). My figure contains an ellipse that is decorated with random steps:  ... \node[ellipse,minimum width=1cm,black!30,decorate,decoration={random steps,segment length=0.2cm,amplitude=.1cm}] {};  \only&lt;1&gt;{ \node (n) at (0,0) {A}; } \only&lt;2&gt;{ \node (n) at (0,0) {B}; }   The ellipse is rendered in differenlty. How can I make it to render the same? or what other decoration can I use to get a similar effect to random steps? For primes $p≡3\pmod 4$, prove that $[(p−1)/2]!≡±1\pmod p$. I know to use Wilson's Theorem and that each element in the second half is congruent to the negative of the first half, but I'm not sure how to construct a proof for it. How to properly ignore exceptions How can I perform a t-test (or another hypothesis test) on NPS (Net Promoter Score) results? Here is an explanation of how NPS is calculated:    I'm interested in testing two net promoter scores to determine if they are statistically different. I read a great answer to calculating margin of error for NPS (see link below), but I'm really interested in testing to see if there is a difference between two scores, because I suspect that our results aren't as "different" from year to year as they appear to be.    Is this at all possible? I understand t-tests are typically used to test whether two different record sets are statistically different. But is it possible to test Net Promoter Scores, either with a t-test or some other hypothesis test?  Any ideas you have would be a great help. Thank you! Problem about angle in isosceles triangle $ABC$ is an isosceles triangle, $AB=AC$, and $\measuredangle A=20^{\circ}$. For point $M$ on $AB$ and $N$ on $AC$, we have $AM=NC=BC$. Compute the  $\measuredangle BMN$.  In a similar problem (with only one point on one side) the key step was to construct an equilateral triangle on the other side. I tried using that in this problem too, but I didn't manage to solve it. $f \in {\mathscr R[a,b]} \implies f $ has infinitely many points of continuity. Pre-generate Review audits to avoid the lag? I had this question:    All 3 responses were rated at 1 when the bounty expired. Nothing got selected as the "best answer", and I can't even manually select an answer.