Unable to update Ubuntu 14.04 to 16.04
14.04 --> 16.04 failed; apt (>= 1.0.1ubuntu2.13)' is not installed
How do I simplify: $$\sum_{r = 0}^{\lfloor \frac{k}{2} \rfloor} \dbinom{k}{2r} \cdot \dbinom{n-k}{k-2r}?$$ Basically, the sum is: $\dbinom{k}{0} \cdot \dbinom{n-k}{k} + \dbinom{k}{2} \cdot \dbinom{n-k}{k-2} + \dbinom{k}{4} \cdot \dbinom{n-k}{k-4} \cdots.$ This seems very similar to Vandermonde's Identity but because we skip two everytime instead of one, I don't see how I can apply it to this problem. I installed ubuntu 16.04 LTS, but there is no ubuntu one software, not in ubuntu software center also..Though it is showing selected in unity tweak tool.How can I get it. Please reply. How to Send Html Emails in Google Spreadsheet Here's an example of a Google Docs Spreadsheet script that sends emails using Google spreadsheets. I want the email Sent in HTML not plain text. Can someone help me out?  function sendEmails() {   var sheet = SpreadsheetApp.getActiveSheet();   var startRow = 2;  // First row of data to process   var numRows = 2;   // Number of rows to process   // Fetch the range of cells A2:B3   var dataRange = sheet.getRange(startRow, 1, numRows, 2)   // Fetch values for each row in the Range.   var data = dataRange.getValues();   for (i in data) {     var row = data[i];     var emailAddress = row[0];  // First column     var message = row[1];       // Second column     var subject = "Sending emails from a Spreadsheet";     MailApp.sendEmail(emailAddress, subject, message);   } } Allow people to answer protected questions if they have earned at least some amount of combined SE rep The purpose of protected questions is, according to the message presented on such a question, "to prevent 'thanks!', 'me too!', or spam answers by new users." The more verbose  agrees on the purpose. And the  says this is why protected questions exist:     Some questions are protected because they are expected to attract   either spam or users -- often new users -- who may mistake the site as   a traditional forum, posting "noisy" answers such as "Thank you" or   "This worked for me" or "I'm also having this problem".   Considering this, shouldn't a user be able to answer protected questions if they have gained at least 10 rep on any stack exchange site? If they've already demonstrated one site that they are familiar enough with the SE Q/A format to not be a drive-by useless answerer, shouldn't that confidence in them carry over to other SE sites?  Or maybe at some level of combined SE rep this restriction should be waived. I find it silly that at 15k+ combined network rep, I'm unable to answer a protected question on a SE site I've just started using. Why is there this strange contradiction between the language of logic and that of set theory? In standard probability theory events are represented by sets consisting of elementary events. Consider two events for which (as sets) $A \subset B$. If an elementary event $x \in A$ takes places then we say that $B$ takes place as well. Since $A \subset B$, $x \in A$ implies that $B$ takes place too.  It seems that when for sets (representing events) $$A \subset B$$ $$then \ A \ implies \ B .$$  On the other hand, if we use the language of logic for the events then $$A \supset B$$ $$ \ means\  that \ A\  implies\ B .$$  Why is this strange virtual contradiction between the language of sets and the language of logic?  (In order to avoid down votes and unplesant comments I reveal that I happen to know that the true translation of the sentence $A \supset B$ of logic to the language of sets (representing events) is $\overline{A \cap \overline B}$.) When and why will a compiler initialise memory to 0xCD, 0xDD, etc. on malloc/free/new/delete? I know that the compiler will sometimes initialize memory with certain patterns such as 0xCD and 0xDD.  What I want to know is when and why this happens.  When  Is this specific to the compiler used?  Do malloc/new and free/delete work in the same way with regard to this?  Is it platform specific?  Will it occur on other operating systems, such as Linux or VxWorks?  Why  My understanding is this only occurs in Win32 debug configuration, and it is used to detect memory overruns and to help the compiler catch exceptions.  Can you give any practical examples as to how this initialization is useful?  I remember reading something (maybe in Code Complete 2) saying that it is good to initialize memory to a known pattern when allocating it, and certain patterns will trigger interrupts in Win32 which will result in exceptions showing in the debugger.  How portable is this? Use SUM In Update Statement I am attempting to use SUM() in my SET statement for my UPDATE.  When I try this, I get an error of      Msg 157, Level 15, State 1, Line 234   An aggregate may not appear in the set list of an UPDATE statement.   What should I alter in my CTE so that I can run this update?    ;WITH CTE AS  (Select EC, CN, CID, EntryDate         FROM OPENQUERY(192.55.108.214,'select                                count(es.estimatenumber) As EC                               ,cm.an CN                               ,cm.am CID                               ,es.entrydate EntryDate                               from etalac es                                INNER JOIN bacalac cm                               ON es.CID = cm.am                               GROUP BY cm.an, cm.am, es.entrydate')) UPDATE d2016 SET TotalNumber = SUM(EC) FROM CTE cte INNER JOIN datafor16 d2016 ON cte.CID = ed2016.CID WHERE CAST(entrydate As Date) BETWEEN '01/01/2016' AND '01/22/2016'; Recursively rename files and directories Previous questions confirmed that Hex can last through multiple encounters (assuming my warlock's concentration doesn't get broken by a club to the head or the like) and at higher levels even through a short rest.   My question is how targeting Hex works when trying to keep it up for extended periods of time.   Can I just cast it on nothing and keep it up until a valid target presents itself or is an initial valid target required?   Then later, does changing the target of the Hex require that the original target is brought to 0 HP?   Once the initial target dies does the spell stay active even if I don't immediately choose a new target?  My suspicion from reading the spell is that it needs an initial target, but then from that point on I can just keep it up after that target dies until it either expires or a new target presents itself. Is this correct? It is said that we can verify time dilation by flying a very accurate clock on a fast jet or spaceship and prove that it registers less time than the clocks on earth. However, the clocks on earth would be moving relative to the clock on the spaceship, and since time always dilates and never goes faster regardless of the direction of relative motion,  the clocks on earth should register less time than the clock on the spaceship.  Is this true? Whenever there is a fast-moving object such as a rocket do all clocks on earth really become slow?  If the rocket with the clock landed after moving at relativistic speed, would its clock and the earth's clock again show the same time since during its travel both appeared slow to each other?  Or is all this just an illusion, ie. the clocks just appear to be slow to each other but in actually run at normal speed, and neither is behind when the rocket actually lands? I know that both can mean "inside" but what I don't have clear is whether both mean the same when talking about time. For example:   The party is in two days = The party is within two days ??   According to this link  within means a limit that can be exceeded, so I'm wondering too if say "the party is within two days max" is correct or redundant. Per-chapter bibliographies in biblatex I'm really new in using biblatex, compile the sample placed in , but what I get is    1.1 Foo    Some text [B02x ].    1.2 Bar    Some text [B02y ].   Do not get the bibliography by chapters, or the global references.  Really not remains to be done   \documentclass{report}  \usepackage[style=alphabetic]{biblatex}  \addbibresource{references.bib}  \begin{document}  \chapter{First chapter}  \section{Foo}  Some text \cite{childs_temperature}.  \printbibliography  \chapter{Second chapter}  \section{Bar}  Some text \cite{hashemian}.  \printbibliography  \newpage  \printbibliography  \end{document}   And the references.bib    @BOOK{childs_temperature,   title = {Practical Temperature Measurement},   publisher = {Butterworth - Heinemann},   year = {2001},   author = {Childs, Peter R N},   address = {Great Britain},   edition = {1},   isbn = {0 7506 5080 X}   }    @PHDTHESIS{hashemian,   author = {Hashemian, Hashem Mehrdad},   title = {Measurements of dynamic temperatures and pressures in nuclear power plants},   school = {{The University of Western Ontario}},   year = {2011},   type = {PhD {T}hesis}   }   I need to obtain references by chapter and global cited references, but i don't know how compile. Field between the plates of a parallel plate capacitor using Gauss's Law make tail -f exit on a broken pipe I want to watch a file until a bit of text appears  I found this answer:   but when I tried it on ubuntu, it doesn't exit:  $ echo one &gt; test.txt $ echo two &gt;&gt; test.txt $ echo three &gt;&gt; test.txt $ echo four &gt;&gt; test.txt $ cat test.txt | sed '/w/ q' one two $   works as expected.  however when I try to tail the file  $ tail -f test.txt | sed '/w/ q' one two   it never exits.  tail does not stop even though the pipe is broken.  Does anybody know how to make tail exit when sed exits? Choosing variables to include in a multiple linear regression model I am currently working to build a model using a multiple linear regression. After fiddling around with my model, I am unsure how to best determine which variables to keep and which to remove.  My model started with 10 predictors for the DV. When using all 10 predictors, four were considered significant. If I remove only some of the obviously-incorrect predictors, some of my predictors that were not initially significant become significant. Which leads me to my question: How does one go about determining which predictors to include in their model? It seemed to me you should run the model once with all predictors, remove those that are not significant, and then rerun. But if removing only some of those predictors makes others significant, I am left wondering if I am taking the wrong approach to all this.  I believe that  thread is similar to my question, but I am unsure I am interpreting the discussion correctly. Perhaps this is more of an experimental design topic, but maybe someone has some experience they can share. Positive correlation and negative regressor coefficient sign Is it possible to obtain a positive correlation between a regressor and a response (+0,43) and, after that, obtain a negative coefficient in the fitted regression model for this regressor?  I'm not talking about changes in the sign of the regressor among some models. The coefficient sign always remains.  Could  the remaining variables of the fitted model influence the changing of the sign? Why does the light side of the moon appear not to line up correctly with the evening sun? I am from Europe, and I did an internship in the US (California) in 2015. When filing my 2015 taxes, I ended up having to pay some small difference for the federal taxes, but got a refund on my state taxes, of roughly $1.6k. That was all the income I had in the US in 2016.  I did not enter the US in 2016 at all.  I managed to figure out that I don't need to file any California tax forms for 2016 (source: ) but I am not sure about federal taxes.  I tried researching the problem, and got some information on it, but the situation is still a bit unclear. It seems that since I listed my state tax as an itemized deduction in my 2015 tax report, which I filed in 2016, the state refund I got in 2016 is, in fact, taxable.  In this situation, would I have to file my taxes (and possibly pay owed tax) for 2016, even though I never set foot in the US in that year, and my total income is just $1.6k? Mean Value Theorem: $\frac{2}{\pi}<\frac{\sin x}{x}<1$ I've doing some researches since few days and I haven't really got an answer to my question.  I am in the process of building a huge file server for the company I work for. We bought a server case  with 24 bays and drives. Now I am stuck at the point where I have to choose the RAID card. I saw a RAID card from LSI that offer 6 internals mini-SAS 8087 ports (6x4) and would work perfectly with my build. However, it's not cheap.  I have been reading about the subject and I found something called SAS Expander. They are cheap.  with 6 mini SAS 8087 for 225$ (instead of 1150$ of the other one).  Now my question, how would I link an SAS Expander with a RAID card ? Do I need to a buy a RAID card with only 1 external 8088 port and link it with the other card ? Could someone clarify this for me because I haven't found any good documentation on it.  Thanks you.