Alternative for AppendTo
What is the best way to flatten a linked list with lists as values?
What I get:  host:~ user$ cat example.txt some texthost:~ stas$   What I want to get:  host:~ user$ cat example.txt some text host:~ stas$   Is there a way I can make cat behave like this?  I'm using bash on Mac OS X. Would you ever stop rolling the die? Singleton: How should it be used \section*[toc]{normal section title} not working for me for my thesis I want to have a section appear differently in the ToC than in the text.  After googling a bit, I found \section[short]{long} as a proposed answer, but this does not seem to work for me.  Here is a MnotWE:  \documentclass[12pt,a4paper,reqno]{amsbook} \usepackage{fontspec} \setmainfont[SlantedFont={Latin Modern Roman Slanted},          SmallCapsFont = {Latin Modern Roman Caps},          ]{Latin Modern Roman}    \usepackage[activate=true,nocompatibility},final,tracking=true,factor=1100,stretch=10,shrink=10]{microtype}  \usepackage[bindingoffset=1cm]{geometry} \usepackage{polyglossia} \setdefaultlanguage{english} \usepackage{csquotes}  \title{\textsc{Some Title}} \author{me}  \begin{document} \maketitle \frontmatter \tableofcontents \mainmatter  \part[toc part]{normal part} \section*[toc section]{normal section} some text  \end{document}   It just takes "toc part" as normal and as ToC heading for the \part command.  For the section I am interested in the starred version. Here the [toc section] part of the command seems to be completely ignored.  I use LuaLaTeX to build my document. Does anyone have a suggestion how to get a \section* appear with a different title in the ToC? How to evaluate $\int_{0}^{+\infty}\exp(-ax^2-\frac b{x^2})\,dx$ for $a,b>0$ Distance from the surface as an input node for use with volumetric materials What are integers $x$ and $n$ such as $ x^4+x^3+x^2+x+1 = n^2$? What are the integer numbers $x$ such as $x^4+x^3+x^2+x+1$ is the square of an integer?  $0$ and $-1$ are obvious answers, but how many are there? Can I create a user-specific hosts file to complement /etc/hosts? Is it possible to add a list of hosts that are only specific to a certain user? Perhaps a user-specific hosts file?  This mechanism should also complement the entries in the /etc/hosts file. Question: If $R$ is a finite boolean ring, then show $R \cong \mathbb Z_2 \times \mathbb Z_2 \times \cdots\times \mathbb Z_2$.   I know that   $\mathrm{char}(R) =2$  $R$ has $2^k$ elements for some $k$  (this is because, if $p\neq 2$ is a prime with $p\mid|R|$, then there exists a non-zero $x \in R$ s.t. $px=0$ and $p $ is odd $\implies x=0$, contradiction).   Does this suffice to answer my question? How can I show that $ab \sim \gcd (a,b) {\operatorname{lcm} (a,b)}$ for any $a,b \in R \setminus \{0\}$? Let $R$ be a UFD. Then for any two elements $a,b \in R \setminus \{0\}$ $ab \sim \gcd (a,b){\operatorname{lcm} (a,b)}$.   My attempt :  Let $d = \gcd (a,b)$.Then $d|a$ and $d|b$.Then $\exists x,y \in R$ such that $a = dx$ and $b = dy$.Now it is to be shown that $c = dxy$ is the lcm of $a,b$.Which I find difficulty to show.It is clear that $a|c$ and $b|c$. Now if $u$ is any common multiple of $a$ and $b$.Then $dx|u$ and also since $y|b$ we have $y|u$ i.e. $dxy|u^2$ $\implies c|u^2$.But I have to show $c|u$ to complete the proof which I fail to prove.Please help me to complete the proof.  Thank you in advance. Is it possible to call the base method from a prototype method in JavaScript if it's been overridden?  MyClass = function(name){     this.name = name;     this.do = function() {         //do somthing      } };  MyClass.prototype.do = function() {       if (this.name === 'something') {         //do something new     } else {         //CALL BASE METHOD     } }; So assume $Y$ and $X$ are exponentially distributed with parameters $y_1$, and $x_1$ respecitively.  assume c is a constant.  I am having huge trouble to understand the integration of the following expression.  $P(Y&lt;c/u(X))$  $=\int_{t}^{\infty}f_X(x)\int_{0}^{c/u(x)}f_Y(y)dydx +\int_{0}^{t}f_X(x)\int_{c/u(x)}^{\infty}f_Y(y)dydx$  where t is the cross-point that $u(x)$ change sign    here $c/u(x)$ is given by the plot below, t is the point crossing the zero:   Confusion:   I don't understand the second integration of the second term "$\int_{c/u(x)}^{\infty}f_Y(y)dydx$", this isn't right because Y an X only defined for y>0, and x>0. So it's the first quadrant in this plot. I've recently read a  from a local paper that included the following:     The pair was drinking prior to the shooting.   To me, this appears wrong and I would say that the proper way to make the statement would be:     The pair were drinking prior to the shooting.   Is the original article correct? Number of ancestors 750 years ago I have 2 ancestors, a father and a mother. Two generations back - 4 ancestors. Three generations back - 8 ancestors.  30 generations back: 2^n = 2^30 = ~1,000,000,000 ancestors.  If a generation is 25 years long, 30 generations are 750 years and 30 generations ago the year was 1,267. But the world population was only 400,000,000 people so how can my math be wrong? and is there a way to estimate the number of ancestors I had 750 years ago? Should I have more than one brokerage account? I have my brokerage business with one particular well-known US brokerage house. I find being able to access my retirement accounts and personal investment accounts through the one interface useful.  However, I was talking with a friend of mine and she said she never puts more than about $50k into any particular brokerage account.  Managing three or four such accounts seems like too much overhead for me. I'd prefer to spend my "investment time" reading up on my investments and researching new ones.  One reason to have more than one brokerage account with different houses is the issue of  insurance:     Within limits, SIPC expedites the return of missing customer property by protecting each customer up to $500,000 for securities and cash (including a $250,000 limit for cash only).   What other reasons could I have to use more than one brokerage account? Oneboxing a onebox from a different chat server generates a weird URL So if you try to onebox a onebox from a different chat server, . Basically, it generates this URL:    Now, obviously that isn't right. I've also tested this , and I'm assuming it's broken on chat.SO too. Can this be fixed? I expect to be working on a web application within the next several months and I'd like to "shoehorn" a Spanish language version of the site. If a large enough number of Spanish language users begin using the site we'll likely hire a professional translator (or at least recruit someone who actually knows the language), but in the meantime is there a good cheat sheet I can use for common UX keywords, like "OK", "Submit", "Cancel", "Delete" and "Save"?  I know I could use an online translator, but I'm concerned the translator would not pick up on context (thus giving me a Spanish word meaning something closer to "Take" for "Accept" or "Surrender" for "Submit", etc.)  I'm not looking for a 100% solution, just something to give me the bulk of the keywords until there's enough reason to hire a real translator. This site will be in a beta development phase for a long time, I think, so we're not expecting a huge user base to start things off. I need to add 30 minutes to values in a Oracle date column.  I do this in my SELECT statement by specifying   to_char(date_and_time + (.000694 * 31)  which works fine most of the time.  But not when the time is on the AM/PM border.  For example, adding 30 minutes to 12:30 [which is  PM] returns 1:00 which is AM. The answer I expect is 13:00.  What's the correct way to do this? Coefficient growth in the power series $\sum u_n z^n = e^{1/(1-z)}$? Take the function  $$ \begin{cases}f(x,y)=(x^2+y^2)/\sin(\sqrt{x^2+y^2}) &amp; \text{when } 0&lt;\lvert (x,y)\rvert&lt;\pi\\   0 &amp; \text{when } (x,y)=(0,0) \end{cases}$$  I got that this function is differentiable at $(0,0)$. I calculated the partial derivatives at $(0,0)$ of which both were $0$ and trying to show the definition of differentiability is not satisfied but I keep getting that it is. Plz help.