In how many ways can $m$ employees be assigned to $n$ projects if every project is assigned to at least one employee?
Calculating the total number of surjective functions
How can I set an external display (monitor) as the primary one? Currently the MacBook's display works as primary, so every application I open gets open on the 13" and I have to drag it to the 24". I also don't have access to the dock on my 24".  Is is possible to turn off the MacBook screen and use only the one attached via DVI?  (I've just connected my 24" HP LP2475w via Mini DisplayPort to DVI to my MacBook Pro 13", which works great except for this one thing.) How to Find Nearby iOS Devices (GPS locations) using same app Since I installed EasyTag on my Arch Linux several other programs use EasyTag instead of Nautilus as filebrowser.  For example, Firefox starts EasyTag if I click on "open containing folder".  Where can I set Nautilus as my "standard file browser"? How can i change formatting of the table of contents to avoid section numbering and section title to overlap?  Document:  \documentclass[10pt,oneside,notitlepage]{book}  % Use Heuristica Font \usepackage{heuristica} \usepackage[heuristica,vvarbb,bigdelims]{newtxmath} \renewcommand*\oldstylenums[1]{\textosf{#1}}   \begin{document}  \tableofcontents  \part{Part one}  \chapter{Chapter Oh} \chapter{Chapter Oh} \chapter{Chapter Oh} \chapter{Chapter Oh} \chapter{Chapter Oh} \chapter{Chapter Oh} \chapter{Chapter Oh} \chapter{Chapter Oh} \chapter{Chapter Oh} \chapter{Chapter Oh} \chapter{Chapter Oh} \chapter{Chapter Oh} \chapter{Chapter Oh} \chapter{Chapter Oh} \chapter{Chapter Oh} \chapter{Chapter Oh} \chapter{Chapter Oh} \chapter{Chapter Oh} \chapter{Chapter Oh} \chapter{Chapter Oh}   \section{Chapter Hi} \section{Chapter Hi} \section{Chapter Hi} \section{Chapter Hi} \section{Chapter Hi} \section{Chapter Hi} \section{Chapter Hi} \section{Chapter Hi} \section{Chapter Hi} \section{Chapter Hi}  \end{document}   Example output: Pgfplots: How to fill area under a curve in a 3d plot similar to \closedcycle in 2d Can't SSH in as root I'm using the default installation of openssh-server for my Ubuntu 14.04 server. I can connect through the console as root like normal, with my username and password. When I try to SSH with the same username/password, however, I repeatedly get Access Denied errors. /var/log/auth.log reports Failed password for root from &lt;ip address&gt; port &lt;port&gt; ssh2, but I'm entering the correct password.  Why can't I connect to the server via SSH, even though the username and password ARE correct? Travel in the Schengen area after my residence card was lost or stolen I have already booked my flight from Italy to the Netherlands through Ryanair. I'm staying in Italy legally and have a carta di soggiorno. However, after booking my flight, my wallet was stolen, which contains all my IDs except my passport. I filed a police report, and I'm trying to get a new residence card. However, I need to go to the Netherlands ASAP. Will Ryanair accept the police report and receipt of getting a new residence card from the post office?  UPDATE (17.07.2014)  Thanks for helping me out. BTW it's OK now. I went to our local CISL here in Florence, Italy, where they process your envelope for renewing your permesso di soggornio or carta di soggiorno (residence permit for foreigners) to be submitted to the post office. That's where you pay and get your postal receipt, and they make an appointment for you at the questura. Anyway, long story short, they processed a application for IMPROVISED residence permit which is good for 30 days to travel within the Schengen area, so all I have to do is go to the questura, bring my travel booking, the police report and copy of my passport. Now I can travel, and it's my first time to fly with Ryanair because I always use Transavia to go to Holland. =) Hope this helps for future persons who will have the same issue with lost or stolen residence permits...Just wish me luck that the questura will process my improvised residence permit immediately. Referencing without captions appearing but keeping numbering How should I setup separate MX records for a subdomain? Let's say I have a domain that I run a web application on, for example cranketywidgets.com, and I'm using  for handling email for people working on that domain, for example, support@ cranketywidgets.com, jane@cranketywidgets.com, joe@cranketywidgets.com and so on.  Google's own mail services aren't always the best for sending automated reminder emails, comment notifications and so on, so the current solution I plan to pursue is to create a separate subdomain called mailer.cranketywidgets.com, run a mail server off it, and create a few accounts specifically for sending these kinds of emails.  What should the MX records and A records look like here for this?  I'm somewhat confused by the fact that MX records can be names, but that they must eventually resolve to an A record. What should the records look like here?  cranketywidgets.com - A record to actual server like 10.24.233.214  cranketywidgets.com - MX records for Google's email applications  mailer.cranketywidgets.com - MX name pointing to server's IP address  I would greatly appeciate some help on this - the answer seems like it'll be obvious, but email spam is a difficult problem to solve. How do I drop root privileges in shell scripts? The "--up" option in OpenVPN is normally used for routing etc. And so it is processed before OpenVPN drops root privileges to run as nobody. However, I am invoking shell scripts that need to run as an unprivileged user.  How do I do that? I have studied , especially polynomial's and tylerl's answers, but I do not understand how to implement. I am working in Centos 6.5, and suid is blocked, both as "chmod u+s" and as "setuid()".  There is an OpenVPN plugin ("openvpn-down-root.so") which enables scripts invoked by the "--down" option to run as root. There could be an equivalent, such as "openvpn-up-user.so", but I have not found it.  Edit0  Per Nikola Kotur's answer, I've installed . Although the chpst command works in terminal, in the up script it fails with "command not found". What works is "sudo chpst" plus setting the proper display and language. Please see  Given that, the up script needs these four lines:  LANG="en_US.UTF-8"; export LANG GDM_LANG="en_US.UTF-8"; export GDM_LANG DISPLAY=:0; export DISPLAY sudo chpst -u user -U user /home/user/unprivileged.sh &amp;   Edit1  Per 0xC0000022L's comment, I find that "sudo -u user" works as well as "sudo chpst -u user -U user":  LANG="en_US.UTF-8"; export LANG GDM_LANG="en_US.UTF-8"; export GDM_LANG DISPLAY=:0; export DISPLAY sudo -u user /home/user/unprivileged.sh &amp;   I'll study man sudoers and update if/when I get sudo alone to work. From the Windows NT-based (Windows XP and 7 specifically) command prompt, how can I get the serial number of a hard drive as a variable? The one I'm looking at is the serial number of the physical hard disk drive How can I see the history of stories I've read on Apple News? Sometimes I'll be interrupted in the middle of reading a story on Apple News and later when I open the app, it didn't save the story I was previously reading. I want to be able to resume reading the article, how can I find it again? I'm trying to change the numbers in problems I write for examples I use in my class as well as assignments. However the problems are still inspired by the textbook. Are the problems sufficiently different from the textbook problems to not have copyright issues? There is also an issue of theorems and definitions. Authors of the calculus textbook certainly did not come up with these things. Is it OK to just copy them down in my lecture notes?  By the way I do share my lecture notes on Piazza and the course I'm teaching is multivariable calculus. Is it possible to get the data off of the hard drive of a PlayStation 3 that has crashed? I have already voided the warranty so I am not worried about that and I have access to quite a few tools.   I have a new PlayStation and a few saves that were not backed up. I am not worried about them but if it is possible I would love to get it moved over.   The old PlayStation will not turn on at all and I think I am going to have to pull the drive. My main concern is if I am able to transfer the files without running into any issues. I have heard that some of the stuff is specific to each PlayStation, is that true? I'm looking for an example of $2$ non isomorphic groups $G_1,G_2$  that are finitely generated and presented that have the same finite quotients (up to isomorphism) .  Thanks lstlisting directly after section start removes margin before next section If I place an lstlisting directly after the start of a (sub)section, the margin before the following (sub)section (title) disappears.  Here is a an example document showing the issue:  \documentclass[twocolumn]{article} \usepackage{listings} \begin{document}  \section{Lorem ipsum} Consectetur adipiscing elit.  \begin{lstlisting} Lorem \end{lstlisting}  Sed quis ante nec mi volutpat congue eu id leo.  \section{Dolor sit amet} Suspendisse at lorem mattis, semper massa id, euismod risus.  \newpage  \section{Lorem ipsum} \begin{lstlisting} Lorem \end{lstlisting}  Sed quis ante nec mi volutpat congue eu id leo.  \section{Dolor sit amet} Suspendisse at lorem mattis, semper massa id, euismod risus.  \end{document}   And you can see the (annotated) result here:    Why is there no margin before the fourth section (title)? Is this a bug in my LaTeX environment (MacTeX-2013), or is this the expected behavior? How should I setup separate MX records for a subdomain? How to curve my mesh I'd like to curve my object, but I'm considering two options.  The first one is to make the object up with lots of vertices, like a sphere can be. The second is to apply some kind of modifier curve to a straight mesh, as I've understood there is such a possibility.  Here's an awesome pen drawing of what I'd like to achieve:    and here's my current even more awesome result:    Rather non-awesomely, they don't quite match. So if someone would kindly point me to the correct method to achieving a nice-looking solution with relatively low polygons, I'd be much enlightened Running shell command and capturing the output What is the opposite of "personification"? I want a word that means the opposite of personification.  What is the correct word for describing people with the characteristics of an object/as if they are objects?  I found the word chremamorphism on some forums, but it doesn't seem to be included in the two online dictionaries I searched.