Is there this ornament in latex?
Totally sweet horizontal rules in LaTeX
Error when using TikZ-Feynman package Today I downloaded and installed the new  package to draw Feynman diagrams. I included the packages   \usepackage{tikz}  \usepackage{tikz-feynman} \tikzfeynmanset{compat=1.0.0} \usetikzlibrary{shapes,arrows,positioning,automata,backgrounds,calc,er,patterns}   into my preamble (changed them already many times).  However, already a simple sample code like  \begin{tikzpicture} \begin{feynman} \vertex (a) {\(\mu^{-}\)}; \vertex [right=of a] (b); \vertex [above right=of b] (f1) {\(\nu_{\mu}\)}; \vertex [below right=of b] (c); \vertex [above right=of c] (f2) {\(\overline \nu_{e}\)}; \vertex [below right=of c] (f3) {\(e^{-}\)}; \diagram* { (a) -- [fermion] (b) -- [fermion] (f1), (b) -- [boson, edge label'=\(W^{-}\)] (c), (c) -- [anti fermion] (f2), (c) -- [fermion] (f3), }; \end{feynman} \end{tikzpicture}   directly gives the error:     Package pgfkeys Error: I do not know the key '/graph drawing/node distance'.   Can you please help me? Thanks in advance! Is every sub-lattice of $\mathcal P(X)$ isomorphic to a sub-lattice of $\mathcal P(X')$ containing singleton sets? Prove : $p$(n│even number of ODD parts)=$p$(n│distinct parts ,number of ODD parts is even ) I'm trying to prove the following Integer Partition claim :   $p$(n│even number of ODD parts) = $p$(n│distinct parts ,number of ODD parts is even) .  So I tried to prove a stronger claim :   $p$(n│number of odd parts) = $p$(n│number of distinct parts) :  Using generating functions :   DISTINCT PARTS =  $$(1+x)\cdot(1+x^2 )\cdot(1+x^3 )\cdot(1+x^4 )\cdot\cdot\cdot\cdot$$  = $$\frac {1-x^2} {1-x} \cdot \frac {1-x^4} {1-x^2} \cdot \frac {1-x^6} {1-x^3} \cdot \frac {1-x^8} {1-x^4}\cdot\cdot\cdot\cdot$$  $$ \frac {1} {1-x} \cdot \frac {1} {1-x^3} \cdot \frac {1} {1-x^5} \cdot \frac {1} {1-x^7} \cdot\cdot\cdot\cdot $$  = ODD PARTS  But I'm not sure regarding the proof , does it really prove that even number of odd parts equals distinct parts ,where number of ODD parts is even ?   Thanks Exporting video to .mov in Blender 2.79 In the past, Blender (at least the Mac version) has had the ability to encode video files as .mov, the format used by Quicktime Player. However, with Blender 2.79 this feature seems to have vanished, for both the Internal and Cycles render engines. The release log happens to have the entry "Video encoding settings have been simplified, along with the addition of a Constant Rate Factor (CRF) mode" which I suppose could be the cause.  Does anyone know what happened—whether it is the aformentioned reason or something else—and how to export videos as Quicktime .mov in Blender 2.79? I've been using gksudo nautilus and sudo nautilus through Alt+F2.   What's the difference? They look very similar! Downgrading MacBook Pro 16” to Mojave Did anyone succeed in installing Mojave on the MacBook Pro 16”? It ships with Catalina but my corporate requires Mojave to connect to the corporate network.  I  but once I select booting from the Mojave external drive I get a “forbidden” icon and the system shuts down. Is there any practical difference between saving at 300ppi or 72ppi? I often see statements in discussions about web displayed image quality that go something like this: "I only upload pictures at 72 dpi and 1200 pixels on the long edge, so if someone copies and prints the image it won't look as good as if it were 300 dpi."  What? Have I missed something here?  Does an image edited and saved/exported with 1200x800 pixels at 300 ppi look any different online than the same image saved/exported with 1200x800 pixels at 72 ppi? Other than the metadata regarding ppi, is there any difference in the two images at all? If so, what is the difference? If I tell my printer to print the images at 4R (4X6 inches) will there be any difference at all in how the printer creates a print from the 1200x800 @ 300 dpi image versus the 1200x800 @ 72 dpi image? If $0 &lt; \alpha &lt; 1$, then       $$ (x + y)^{\alpha} &lt; x^{\alpha} + y^{\alpha} $$      for $x$, $y$ positive.   Is this inequality true in general?  I tried using Young's Inequality: For $z,t &gt; 0$, and for $n$, $m$ such that $n+m=1$, then   $$ z^n + t^m \leq nz + mt $$  So, using this we have   $$ (x+y)^{\alpha} \cdot 1^{1 - \alpha} \leq \alpha(x+y) + (1-\alpha) = \alpha x + \alpha y + (1-\alpha)$$  which is not as tight as I want. How should different sized RAM be added to iMac? I have a mid-2011 iMac which came with 4GB RAM (2x2GB). I just bought 8 GB (2x4GB) and added it to get a total of 12GB. The current configuration is as follows:    Given that the RAM is a different size, do I have the optimal locations for the different RAM chips? At the moment what I did was to simply add the 2 new sticks of RAM in the two empty slots. jQuery get all divs which do not have class attribute How to add custom C++ keywords to be recognized by Minted? I have defined several structures and types in a C++ project. I have to write some documentation for this code, and I use  to typeset my code.   I would like to be able to add some keywords to the minted database, so minted will also recognize these and give them the appropriate color. (I would like to have them colored in the same way a type, eg. double would be colored.) What's the difference between "Service" and "/etc/init.d/"? How do I get money back for my foreign coins? Tonight I just cleaned my room and while doing this I found some money. I counted it and I found out that there are a lot of coins from 25 different countries.  I know that normally banks don't exchange foreign currencies in coins, but is there a way so that I can still get some money for my foreign coins? Marking plural of code words In my blog (which is about programming) I often use reserved words from different programming languages.  Like this:     When column is nullable in both tables, this query won't return a match of two NULLs for the reasons described above: no NULLs are equal.   Here, NULL is a programming language keyword.  For numerous reasons, I mark them with &lt;code&gt; tag so they are rendered with a fixed width font, not translated into the foreign languages by Google Translate, can easily be seen on the page etc.  In the example above, which would be the best way to mark the plural?   NULLs NULL s NULL's NULLs NULLS   Option 1 looks ugly on the page (the word and the plural marker are rendered in different colors and fonts)  Option 2 adds a space between the word and the plural marker  Option 3 looks nicest but is not correct  Options 4 and 5 may leave the reader under impression that NULLS is a reserved word (which is not true) and this may be confusing. Also, Google Translate would leave the word as is which would be definitely wrong in other languages.  What would be the least of 5 evils? What are the rules for calling the base class constructor? What are the C++ rules for calling the base class constructor from a derived class? For example, I know in Java, you must do it as the first line of the subclass constructor (and if you don't, an implicit call to a no-arg super constructor is assumed - giving you a compile error if that's missing). Is better healthcare a bane to the long-term survival of the human race? The theory of natural selection has it that individuals with better genes tend to survive and reproduce, passing their genes to their offspring. This gradual process results in a population more adapted at survival. However, due to the advancement in medical science, humans with poorer genes tend to survive and reproduce just as well.  For example, in the past, many people, excluding those with natural immunity due to some genetic mutations, would have succumbed to illnesses such as malaria and typhoid. But with better hygiene and medical treatment, these patients tend to survive.  Now, imagine a future where all illnesses including cancer can be treated. How would it impact the survival of the human race? Would we become more and more vulnerable such that our survival hinges heavily on medical technology, analogous to how an astronaut's survival is dependent on his spacesuit? Every time I read the tips for installing an SDK, IDE, some extension and so on, it says, that I should unpack them in /opt folder. Why do I need to do that?   When I was installing Ubuntu, I read that I should set only 10-20 GiB for the / file system and remaining space set for /home. So should I extend the space for root folder, or leave all stuff at /home? Is there any difference? Stack Overflow has left! I'm trying to to execute a script, which uses the command rename.   When I execute it, I get a message rename: command not found. Any ideas?   if [[ -z '$3' ]]; then     shopt -s dotglob     rename "$EXPRESSION" ./* else     rename "$EXPRESSION" "$3" fi $\sum\limits_{n=1}^{\infty}\frac{1}{1+z^n}$, $|z|&gt;1$.  There are two facts that my professor uses that I am confused about.  The first is: $|1+z^n| \geq ||z|^n-1|$, I believe this is true for any $|z|$.  The other is: $\frac{1}{|z|^n-1} \leq \frac{2}{|z|^n}$, I believe this is also true for any $|z|$.  Can anyone prove these statements for me?