planar graph of Submultiples
When is the graph of the divisor relation on $[n]$ planar?
When will data.SE get updated data? promised that data.SE would &quot;soon&quot; get live data:     I realize it's a long weekend, but given that data.SE is now over 2 months out of date, it would be nice if this was finally rolled out. How can I disable a USB port in Windows XP to make it available only for smart phone battery charging?   I don’t want the users to be able to see the USB drive in My Computer, and the USB device should stay disabled in Device Manager.   Is there any way to accomplish this? Writing a function inside the main method - Java Term for a person who can read but cannot write I'm looking for a term to accurately describe a person who can only read but cannot write. While I'm primarily concerned with people who have never learned to write, I would also be interested in any additional terms used to represent people who have lost the ability to write as a result of disuse.  Both illiterate and unlettered imply an inability to read as well as to write. How do I set up SSH so I don't have to type my password when connecting to a host? How can I String.Format a TimeSpan object with a custom format in .NET? What is the recommended way of formatting TimeSpan objects into  a string with a custom format? What regulations should a European driver know when driving in the US? There are the obvious ones. The US has the keep-your-lane system, where as in Europe you are expected to keep to the right (left for UK) as long as possible.  On my latest travel to the US, I was confronted with the possibility to go through a red light if you turn right, unless it is explicitly not allowed.  What should a european driver know when driving in the US? What are the do's and don'ts compared to driving in Europe. Redirect www to non-www using Apache htaccess does not work How do I use RelativeSource with WPF bindings and what are the different use-cases? Tag hierarchy to browse through tags Possible Duplicate:          Since so many thousands of tags and topics exist, it would be really useful to visually browse through tags by organizing them into a , or hierarchical map. This drill-down map would make it easier to find the tag/subtopic you want or just generally browse within the topics you're interested in.  So we could nest all "visual-studio-2008" and "visual-studio-2003" tags into "visual-studio", which would be under "dev-tools". Something like how Wikipedia's categories have sub-categories. Create SOAP envelope of XML and send it as HttpWebRequest to WebService I am trying to calculate the last two digits of $3^{400}$, but working $\bmod {100}$ is proving intractable. I did the last digit case pretty handily, and now I'm stuck at last two. How to avoid the 'not properly formatted as code' alert Why is $(2, 1+\sqrt{-5})$ not principal? Why is $(2, 1+\sqrt{-5})$ not principal in $\mathbb{Z}[\sqrt{-5}]$?   Say $(2,1+\sqrt{-5})=(\alpha)$, then since $2\in(2,1+\sqrt{-5})$ we have $2\in (\alpha)$, so $\alpha\mid2$ in $\mathbb Z[\sqrt{-5}]$. Writing $2=\alpha\beta$ in $\mathbb Z[\sqrt{-5}]$ and taking norms, $4=N(\alpha)N(\beta)$ in $\mathbb Z$, so $N(\alpha)\mid4$ in $\mathbb Z$. Similarly, since $\sqrt{-5}\in(\alpha)$ we get $N(\alpha)\mid5$, thus $N(\alpha)$ is a common divisor of $4$ and $5$, therefore $N(\alpha)=(1)$, so $\alpha$ is a unit. But that means $1\in (2,1+\sqrt{-5})=(\alpha)$, so it must be the whole ring, but it cannot to reach a contradiction, so how can I find an element, which is not in $(2, 1+\sqrt{-5})$.  Or is there a simpler method ? (Maybe not UFD would imply not PID) How exactly do I install Minecraft Mods and what is Forge? Proof: How many digits does a number have? $\lfloor \log_{10} n \rfloor +1$ I read recently that you can find the number of digits in a number through the formula $\lfloor \log_{10} n \rfloor +1$ What's the logic behind this rather what's the proof? When is it appropriate to create an entity instead of a new content type? What is the benefit to creating new entity types over just building a new content type?    It seems a bit overkill to do all of the custom coding that is required to create a new entity when you have all of the CRUD and Views functionality already built into content types. Router to router setup works fine with straight cable up to 2-3 meter it is not working for 45 meter why? How can I download a Flash video from a website? What are the dangers of accepting gifts from unknown accounts on Steam? A user named 'steamfairy1' gifted me a game on Steam. I don't know this user, their profile shows no games, no friends and zero hours played. The profile of 'steamfairy1' was created the day I received the gift.  It very much looks like a scam, but I can't figure out how the scam is supposed to work. What's the worst thing that could happen if I accept the gift? Any idea what the trick here is? It could be just a random act of kindness and I'm just paranoid…  I contacted the Steam support, but they were unhelpful as usual: responding in the wrong language and with a canned one-liner that didn't make a whole lot of sense or had much to do with my question.  Keywords (not really tags, but I want this to be searchable): steamfairy, steam fairy