This is a silly question but can you install software from debian packages without having an internet connection ?
I have a friend who has got a computer that is not connected to the Internet. Is there any way to install software offline easily?
Prove that$$\overbrace{\binom n 0 + \binom n 1 + \binom n 2 + \cdots + \binom{n}{\frac{n-1} 2}} + \overbrace{\binom n {\frac{n+1} 2} + \cdots + \binom n {n-1} + \binom n n} = 2^n. $$   Background:  This problem came from the following link:    and I didn't understand why that was true in which no one on the page has proved it to be so. and i was wondering what was the proof on that How do I move Steam games to a new computer without re-downloading them? Bluetooth audio delay / lag, reason completely unclear to me I have a bit of an odd situation, and wanted to ask for ideas.   Recently started connecting a JBL Charge 2+ to my MBA 11 inch, mid-2013, via Bluetooth. I noticed that there's clear delay between sound event and sound being audible via the JBL.   The problems persists across applications (so for example, playing video via VLC means the sound isn't synced, same for youtube videos in different browsers, same for mp3s that start playing with a small delay, etc.)  The delay is minor, but noticeable, in the range of 0.5s I'd say.  At first I thought it might be a Bluetooth driver issues, but now I found out the following: just connected another JBL device, a Flip 3 to the same MBA, and the sound plays without noticeable delay. I'm not sure if they use the exact same drivers, but now I'm wondering:   Is there a chance that it's a hardware problem? Didn't really consider this a possibility, but now I'm not sure anymore. How to test, and, ideally, fix this issue? How can I isolate the reason for the audio lag with the Charge 2+?   Any help would be appreciated! A Polygon is inscribed in a circle $\Gamma$ A regular polygon P is inscribed in a circle $\Gamma$. Let A, B, and C, be three consecutive vertices on the polygon P, and let M be a point on the arc AC of $\Gamma$ that does not contain B. Prove that  $MA\cdot MC=MB^2-AB^2$  I inscribed the polygon P in the unit circle and let B=1. Past this, I'm not really sure how to proceed. It might be helpful to have M at 1 as well but given that the polygon would have the n-th roots of unity in it B seemed like a good choice. What would be a good way to proceed from here? I want to shrink my second (LVM) partition, in order to create a new partition in the newly freed space. I am using the Live CD to do so, because I know I can't resize/move this partition while it is in use. When I opened GParted in the Live CD, I realized that I could not resize the partition, because when I right-click it, the option "resize/move" is disabled.  I tried to unmount it, to "lazy" unmount it (umount -l /dev/sda2) but it didn't work.  A screenshot from GParted: Using single quote by curly braces in String.format in Dynamic SOQL I'm struggling to use String.format to replace a token with a value when the token is within single quotes:  Example:  String query = String.format('SELECT Id FROM Availability WHERE Person__c = \'{0}\'', personId);   String query is equal to:  SELECT Id FROM Availability WHERE Person__c = {0}   Rather than:  SELECT Id FROM Availability WHERE Person__c = '234567890' We've heard it many times, nothing can escape the gravity of a black hole, even light once it's past the event horizon.  If this is true, how can a black hole emit anything?  are massive black holes that have consumed enormous amounts of matter and energy, and then blasted it back out into the universe.  How is this possible?  Time stands still in a black hole, that in itself should stop anything from moving. Can anyone explain reverse bias pn junction using only electrons as charge carriers In forward bias condition p-type semiconductor is connected to positive side and ntype semiconductor to negetive side and the electrons flow from n-type to p-type to cathode of battery.  But imagine the same situation when the situation is reverse biased so now p-type is connected to negetive terminal of battery and n-type to positive terminal of battery.  Now there is excess of electrons in n-region and it is connected to positive terminal of the battery.So electron can flow from n-type region to positive terminal of the battery due to potential difference created by battery whereas in p-type electrons can flow from one covalent bond to another as they do in forward biasing.  Only difference is,here electron move in opposite direction (from one covalent bond to another) i.e. from n-region to depeletion region whereas in forward bias they move from depeletion to n-region.Which shouldn't be a problem   Now in this manner current must flow regardless of biasing so what's the correction? Package Listings Warning: Text dropped after begin of listing when calling function I'm trying to this:  \newcommand{\code}[1] {\begin{lstlisting} {#1} \end{lstlisting} }   But I keep getting this error:  Package Listings Warning: Text dropped after begin of listing   I'm calling \usepackage and all so, do any of you knows how to solve this? Is "of" instead of "have" correct? Factoring Quadratics Is there a method to find which numbers to use when simplifying quadratics?   For example $x^2 + 5x + 6$ is easy enough to find, but what if I have bigger numbers, or I have this quadratic expression: $x^2 + 7x – 6$, then it gets very hard to think of a valid simplification.  EDIT: Here's an example: $(x^2 + 5x + 6)/(x + 2)$. When simplifying the first half we get $(x + 2)(x + 3)/(x + 2)$, then we can cancel out $(x + 2)$ and the answer would be $(x + 3)$. The question is: How to always find the right numbers which to put in? (in this example they where 2 and 3) Does MariaDB or MySQL implement the VALUES (expression) table value constructor? Check for column name in a SqlDataReader object How do I check to see if a column exists in a SqlDataReader object?  In my data access layer, I have create a method that builds the same object for multiple stored procedures calls.  One of the stored procedures has an additional column that is not used by the other stored procedures.  I want to modified the method to accommodate for every scenario.  My application is written in C#. How to copy the complete folder structure one location to another location include all files and sub folders I have folder structure like in Shared documents/East using CSOM and C# Main Folder   Folder1   Folder2      File1      File2  I have to copy all folders with files to Shared documents/West .... How do i prove that continuous linear transformation between normed spaces is bounded? Let $(V,||\cdot||_V),(W,||\cdot||_W)$ be normed spaces over $\mathbb{C}$.  Let $T:V\rightarrow W$ be a linear transformation.  Assume $T$ is continuous.  Then, how do i prove that $\exists c&gt;0$ such that $\forall v\in V, ||Tv||_W&lt;c||v||_V$? Calculate probability (area) under the overlapping area of two normal distributions newcommand vs. DeclareMathOperator As far as I understand, whatever can be done using DeclareMathOperator can also be achieved using newcommand, but not the other way around. If this is the case, what are the circumstances where DeclareMathOperator is the better choice? When should I take solely newcommand?  I found a question regarding , and I wonder what other aspects should be taken into consideration when it comes to choosing which method to use when defining math operators. Is it true every ideal of $\mathbb{Z}[x]$ is finitely generated? Let $I$ be any ideal of $\mathbb {Z}[x]$, and $I=\left&lt;{f_1,f_2 , ...}\right&gt;$.  Without loss of generality, $f_1$ has minimal (absolute value) coefficient of constant term (if there exist).  Then, let $g$ be any element of $I$ .  We have for some integer $m$ that $g - mf_1$ is element of $I$ (minimal coefficient and division algorithm).  I guess this process terminate finitely, but I don't know how can I do next step.  ( ex. $g-mf_1, g-mf_1-nf_2, ...$)  Please help me and thanks for in advance. Accidentally ejected External drive while downloading file, now having problems reading I'm hoping someone can help! I recently downloaded a torrent directly onto an external hard drive, (using a 2009 MacBook Pro and 1TB Seagate Expansion portable Drive) somehow during the download the drive was accidentally ejected, since this incident when I plug the drive back in it’s having problems reading.  The drive works fine for about 10 minutes, I can read/copy/paste and access files but then starts to wreak havoc; apps hangs, it hangs the Finder, etc.  I’ve tried repairing it in Disk Utility, which reads and repairs this disk but problems inevitably continue as described above.  I’ve deleted the Torrent file also. All my files on this external drive so re-formatting is not an option until I can retrieve them. Problem storing arrays with update_user_meta I am writing a function that adds an ID number to an array and puts the array in the usermeta. $_GET['auction'] is the post_id.  Below is the function:  $reminders = get_user_meta( $current_user-&gt;ID, "reminders" ); print_r( $reminders ); if( in_array( $_GET['auction'], $reminders ) ) {     echo "Failed: Auction already in list"; } else {     array_push( $reminders, intval( $_GET['auction'] ) );     if ( update_user_meta( $current_user-&gt;ID, "reminders", $reminders ) ) {         echo "Success";     } else {         echo "Failed: Could not update user meta";     } } print_r( $reminders );   Here is the output after adding one auction:  Array ( )  Success Array ( [0] =&gt; 7 )    Here is the output after adding two auctions:  Array ( [0] =&gt; Array ( [0] =&gt; 7 ) )  Success Array ( [0] =&gt; Array ( [0] =&gt; 7 ) [1] =&gt; 73 )   And here is the output after adding three auctions:  Array ( [0] =&gt; Array ( [0] =&gt; Array ( [0] =&gt; 7 ) [1] =&gt; 73 ) )  Success Array ( [0] =&gt; Array ( [0] =&gt; Array ( [0] =&gt; 7 ) [1] =&gt; 73 ) [1] =&gt; 0 )   Notice that adding a new element to the array using array_push works fine. But when the array is stored in the usermeta then retrieved again, the last element in the array has been put into an array of its own, creating an infinitely dimensional array. I'd prefer to keep this array one dimensional.  Is there a way I can run update_user_meta and get_user_meta without it changing the structure of my array?