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Chance of selecting the last k pages in correct order from a set of n pages How do I create a 50x3 cell array from a 50x3 matrix. Keep just getting a 1x1 cell array with a 50x3 submatrix? What's the difference between "Service" and "/etc/init.d/"? Can spells be cast through a Wall of Force? Simple question about the definition of Brownian motion I have a question concerning the definiton of Brownian motion. Usually (e.g. on Wikipdia) one demands a brownian motion $\lbrace B_t\rbrace_{t\in[0,\infty)}$ to satisfy the following condition:  $\forall 0\leq t_0&lt;t_1&lt;...&lt;t_m: B_{t_1}-B_{t_0},...,B_{t_m}-B_{t_{m-1}}$ are independent random variables.   But today I come across with formally another definition of Brownian motion! Instead of the above condition the book demands the following property:  $\forall t,h\geq 0$, $B_{t+h}-B_t$ is independent of $\lbrace B_u : 0\leq u\leq t \rbrace$.  Now I'm wondering whether both properties are indeed equivalent or not?! Hopefully someone can help me. User suggested great corrective edit to my answer, but the edit was rejected. What can I do to approve it? A nice user suggested  to . The edit, though very good and desirable, was rejected. I do not understand the reasons, and I did not find a way to contact those people who rejected it. What can I do to re-approve the edit? How to insert page number in Beamer navigation symbols? In what order should Tolkien's writings on Middle-earth be read? Privacy leak in permalink? Update (Jan 8, 2019) This is now 8 years old, but still getting occasional upvotes/attention, so I thought it's worth giving a summary of the current state.  Despite originally being , over the last decade some changes have made the privacy implications much clearer.  You now click &quot;share&quot; instead of &quot;link&quot;, and the pop-up is very explicit that the link includes your user ID. There is a  asking that this user ID be anonymized or hashed, to allow users to earn publicity badges (the intention behind having the user ID present in the URL, as per ) while eliminating the privacy issue. Original Post It seems to me there is something of a privacy leak when permalinking to a question.  For what I would assume is the purposes of tracking which user is responsible for bringing traffic back to an SE site (for badges, etc.), the user ID of the user obtaining the permanent link . I wouldn't argue that this shouldn't be the case, but I find no warning or mention of this when I do these actions.  I'm sure I'm not the only one that doesn't desire anonymity on SO but would like at least pseudonymity on some places I might share a SO link, such as on a random blog.  As a user, I would not expect sharing a permanent link to leak my identity.   Unless you are familiar with Stack Exchange links or your own userID, it's certainly not obvious by looking at the link that it includes your personal info.  It'd be nice to have fair warning that using that feature will do so, and perhaps provide/describe the workaround: to simply remove the user-id segment from the URL.  Other features would be a preference that formats future permanent links to exclude the user id. Example (from this question)  Permalink:  Link to my user page: Every package "has no installation candidate" While attempting to install openssh-server on Ubuntu 14.04 64-bit, I get the following error:  Package openssh-server is not available but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source  E: Package 'openssh-server' has no installation candidate   I see the same error when trying to install any package.  This is the sources.list file:  deb http://archive.canonical.com/ubuntu hardy partner deb-src http://archive.canonical.com/ubuntu hardy partner Expanding code in etoolbox's \ifblank I am trying to use the etoolbox \ifblank (and its cousin \notblank), but I want to expand any macros in its test statement.  For example:  \documentclass{article} \usepackage{etoolbox}  \begin{document}  \newtoggle{longformt} \newcommand{\longform}{\toggletrue{longformt}} \newcommand{\iflong}[2]{\iftoggle{longformt}{#1}{#2}}  \newcommand{\quoteifnotblank}[1]{%     \notblank{#1}{``#1''}{}% }  % Try commenting this line. \longform  This should be completely blank if the form is short: \quoteifnotblank{\iflong{Some long quoted text}{}}  \end{document}   The problem here is that \notblank sees its argument of \iflong{Some long quoted text}{} as a string, not as code to be expanded, so the quotes always appear.  How do I expand arguments before they are passed to \notblank? As I finished programming the MCU in the Arduino Uno board to receive some RF Signal and drive relays, I moved it into a standalone board I made with Eagle. The circuit is pretty basic, the MCU receives data from a RF Receiver, processes it and then turns on/off some pins that drive 5V relays (through transistors, of course). When I test it on the Arduino Board, you can see that the LEDs toggle ON and OFF whenever I send the data through the RF Transmitter. You send once, it toggles ON, you send another time, it toggles OFF and so on. This works for all the 4 PINS that it has programmed. In my standalone board, each of these four pins are connected to transistors that drive 5V relays. The problem is that only one pin seems to activate, and then it won't even toggle OFF, like you send the data once and you can hear the relay's coil go ON, but then if you try to toggle it OFF it just won't, it's latched ON and I have to unplug and plug the USB cable again to reset it. The ATMEGA328P has a 16MHz crystal, two 22pF caps for the crystal, and a 10K resistor that goes from the Reset Pin to VCC. I'm not sure why the MCU behaves so weird in my board. There's also another VERY weird detail I didn't mention. If instead of using the RF Receiver, I connect the Data Output pin of the PIC that drives the RF Transmitter directly into the Receiver board, that one pin I mentioned that works is able to toggle OFF and ON again, but still, the other pins just don't work. I've tested it not only by hearing the relay's coil but also by using a multimeter. Any help would be really appreciated.  EDIT:  Here is the Eagle Schematic of the board:    It's true that I really didn't concern about the noise, but since it was quite a simple project I didn't think that noise was going to attack so violently, plus  I don't really know how to protect the circuit from inductive noise. Thank you for answering fast!  EDIT 2:  Okay so here goes more detail:    Real photos:      The soldering seems quite awkward but I probed all the traces to check for continuity.  I could make some extra holes to, for example, add a 100nF decoupling capacitor for the MCU and so, but if you think I should enhance the schematic and add a lot more components, then I'll gladly remake the board.   About the supply, right now (for debugging) I'm connecting the Arduino Uno to a Cellphone Charger (Notebook won't supply enough current for relays), and I'm connecting those red and black cables to the Arduino Uno. I'm using that Cheap 433MHZ RF Receiver so if the circuit is so vulnerable to noise as you say, it may also be getting fouled up by the noise. Did this character lose a limb in “The Force Awakens?” Inspired by  which states limb loss as a recurring theme, I started thinking about the final lightsaber battle. After watching The Force Awakens the second time, I was not sure if      Kylo Ren   lost a limb or just lost his lightsaber. We definitely see      Rey slash at Ren’s right hand.   So knowing that context:      Did Kylo Ren actually lose his arm/hand? Fix formatting errors of page number > 99 in table of contents? This is a follow up question of .  The formatting problem has nothing to do with cleanthesis.sty.  The problem is that if I use the charter font, page numbers greater than 99 are not formatted correctly in the table of content.  \documentclass[draft=on]{scrbook} \usepackage{blindtext} \usepackage{charter}  \listfiles  \begin{document} \tableofcontents \section{Section 1} \blindtext[100] \section{Section 2} \blindtext[500] \section{Section 3} \end{document} Segmentation fault error occurs for a simple function I have coded How to install Windows 10 Home 19018 update? I'm using windows home edition, I have the latest update installed 1909.  I want to install docker for windows 10 home edition. It keeps saying  Docker Desktop requires Windows 10 Pro/Enterprise (15063+) or Windows 10 Home (19018+).  Should I join Windows insider? How long should I wait for that update to be released if I don't want to join windows insider? Prove that:   $$p \,\,\left|\, {p \choose k} \right., \quad 0&lt; k \lt p$$   if $p$ is prime.   how to prove that with direct proof? What is "#!' in a script file? $cat shebang.sed  #! /bin/sed -f s/red/xxx/ s/BLUE/1234/  $./shebang.sed rgb lower (#1): "xxx green blue" UPPER (#2): "RED GREEN 1234"  $sed -f shebang.sed rgb lower (#1): "xxx green blue" UPPER (#2): "RED GREEN 1234"   I may guess what #! is doing. However, I don't say I know it. what is "#!"? evaluate $\int_{0}^{\infty}\cos(t) t^{z-1}dt=\Gamma(z)\cos(\frac{\pi z}{2})$ Alternative to LibreOffice Base for Ubuntu