Command block shovel how to make it able to destroy course dirt
How to get a tool that can only break specific blocks and has a name?
Strange Recurrence: What is it asymptotic to? So I have the following recurrence relation for the growth rate of an algorithm:  $T(n)$ = time taken by algorithm to solve problem of size n:  $$T(n) = T(n-1) + T(\lceil(n/2)\rceil)$$  Clearly this does not obey any polynomial law but now my question is what does it obey?  I merely want an asymptotic equivalence.  My guess is subexponential since this is faster than polynomial but clearly slower than any exponential form.  What though is the question.... Can a magus with a high BAB cast two spells or attack and cast, with their full attack action? Suppose you are a level 10 Magus or something similar. (Something with a decent BAB progression and spellcasting abilities) When you hit +6/+1, can you cast a spell, then attack, vice-versa, or simply case two spells? Everywhere I look I can't get a clear answer. When is the graph of the divisor relation on $[n]$ planar? Prove that $\sum^{n}_{r=0}(-1)^r\cdot \large\frac{\binom{n}{r}}{\binom{r+3}{r}} = \frac{3!}{2(n+3)}$ Prove that $\displaystyle \sum^{n}_{r=0}(-1)^r\cdot \large\frac{\binom{n}{r}}{\binom{r+3}{r}} = \frac{3!}{2(n+3)}$   $\bf{My\; Try::}$ We can write $$\frac{\binom{n}{r}}{\binom{r+3}{r}} = \frac{n!}{r!\times (n-r)!}\times \frac{r!\times 3!}{(r+3)!} = \frac{3!\times n!}{(n-r)!\times (r+3)!}$$  So our sum is $$ 3!\sum^{n}_{r=0}(-1)^r\frac{n!}{(n-r)!\times (r+3)!} = \frac{3!}{(n+1)(n+2)(n+3)}\sum^{n}_{r=0}(-1)^r\frac{(n+3)!}{(r+3)!\times (n-r)!}$$  So we get Sum $$ \frac{3!}{(n+1)(n+2)(n+3)}\sum^{n}_{r=0}(-1)^r\binom{n+3}{r+3} = -\frac{3!}{(n+1)(n+2)}\sum^{n}_{r=0}(-1)^{r+3}\binom{n+3}{r+3}$$  $$  = -\frac{3!}{(n+1)(n+2)(n+3)}\left[-\binom{n+3}{3}+\binom{n+3}{4}-\binom{n+3}{5}--.......+(-1)^{n+3}\binom{n+3}{n+3}\right]$$  $$=-\frac{3!}{(n+1)(n+2)(n+3)}\left[\binom{n+3}{0}-\binom{n+3}{1}+\binom{n+3}{2}-\binom{n+3}{3}+\binom{n+3}{4}-\binom{n+3}{5}--.......+(-1)^{n+3}\binom{n+3}{n+3}\right]+\frac{3!}{(n+1)(n+2)(n+3)}\left[\binom{n+3}{0}-\binom{n+3}{1}+\binom{n+3}{2}\right]$$  So we get $$ = \frac{3!}{(n+1)(n+2)(n+3)}\left[1-(n+3)+\frac{(n+3)(n+2)}{2}\right] = \frac{3!}{(n+1)(n+2)}\times \frac{n^2+3n+2}{2} = \frac{3!}{(n+1)(n+2)(n+3)}\times \frac{(n+1)(n+2)}{2} = \frac{3!}{2(n+3)}$$  Can we prove it Using Combinatorial way,bcz above method is very lengthy  If yes then plz explain here  Thanks Copy files from Network Mapped Drive I am trying to copy a file over from a mapped drive on a network to the current computer through a batch file.   I've already attempted the following below and still no results. The plan is to run a batch file to copy a file from a network drive down to the local C:\ drive.   @echo off copy H:\Videos\TargetVideo\TargetVideo.mp4 C:\Video\ Add additional sub-groups to the new Badge page & related Feedback On the  (A+), there are sub-groups under the major groups.  For example, the Participation Badges group has related badges Commentator and Pundit sub-grouped, and Quorum and Convention sub-grouped.  I am of the opinion at least 1 of the following additional sub-groupings should be made:  Question Group   Student &amp; Scholar Investor &amp; Altruist Promoter &amp; Benefactor   Alternately, one sub-group of Investor, Altruist, Promoter &amp; Benefactor    Answer Group   Teacher, Enlightened, Guru Consider moving Generalist to Tag Badges Group or the bottom of the Answer Group if Tag Badges is moved immediately below Answer Group.   Participation Group   Talkative &amp; Outspoken Caucus &amp; Constituent Precognitive &amp; Beta   Tag Badges  Move this group to either the bottom of all groups or below the Answer Group. Its current placement here creates a weird artificial barrier, especially with users who have no Tag Badges.  Moderation Group   Informed &amp; Analytical Taxonomist &amp; Synonymizer Critic &amp; Supporter Disciplined &amp; Peer Pressure Suffrage, Vox Populi &amp; Civic Duty   Alternately, one sub-group of Critic, Supporter, Suffrage, Vox Populi &amp; Civic Duty  add Cleanup and Organizer to the Editor sub-group add Citizen Patrol to the Deputy sub-group   NOTE: Since this is now status-completed, but only a select portion was completed, the rest of the request has been broken into 2 additional questions: How to get from Heathrow Airport to King's Cross, London? My wife and I will be arriving in London via Heathrow Airport (LHR) and are staying at a hotel near King's Cross station. So, we were wondering what the best (which means fastest but also easiest when carrying two large pieces of luggage and two carry-ons) way to get from LHR to King's Cross?  I gather that, with only one changeover, we can take the Tube. However, in the interest of other passengers, we thought it would be best to take a taxi, or maybe a bus?  Thoughts? Film about some dude who fell in love with a star (a literal stellar object) Yes, the plot is pretty weird. There is this "star" (whose incarnation is a woman dressed in white) and some random guy who falls in love with her. There's the arc of "if you cross a specific border you'll die" which applies to our lady "star". Well, I also remember that they have some kind of a tubular case, and when one opens it, lightning files out.  I watched the film somewhere around 2010, it's in English and when I try to remember it, I get the vibe of a mediocre Hollywood fantasy romance. Why is it impossible to override a getter-only property and add a setter? Why is the following C# code not allowed:  public abstract class BaseClass {     public abstract int Bar { get;} }  public class ConcreteClass : BaseClass {     public override int Bar     {         get { return 0; }         set {}     } }      CS0546 'ConcreteClass.Bar.set': cannot override because 'BaseClass.Bar' does not have an overridable set accessor Error in pip: unsupported operand type(s) for -=: 'Retry' and 'int' I'm trying install the requests, but I can't do that. I'm using Ubuntu 16.04  I tried to install using  $ sudo pip install requests   and I get the following error   Collecting requests Exception: Traceback (most recent call last):   File "/usr/lib/python2.7/dist-packages/pip/basecommand.py", line 209, in main     status = self.run(options, args)   File "/usr/lib/python2.7/dist-packages/pip/commands/install.py", line 317, in run     requirement_set.prepare_files(finder)   File "/usr/lib/python2.7/dist-packages/pip/req/req_set.py", line 360, in prepare_files     ignore_dependencies=self.ignore_dependencies))   File "/usr/lib/python2.7/dist-packages/pip/req/req_set.py", line 512, in _prepare_file     finder, self.upgrade, require_hashes)   File "/usr/lib/python2.7/dist-packages/pip/req/req_install.py", line 273, in populate_link     self.link = finder.find_requirement(self, upgrade)   File "/usr/lib/python2.7/dist-packages/pip/index.py", line 442, in find_requirement     all_candidates = self.find_all_candidates(req.name)   File "/usr/lib/python2.7/dist-packages/pip/index.py", line 400, in find_all_candidates     for page in self._get_pages(url_locations, project_name):   File "/usr/lib/python2.7/dist-packages/pip/index.py", line 545, in _get_pages     page = self._get_page(location)   File "/usr/lib/python2.7/dist-packages/pip/index.py", line 648, in _get_page     return HTMLPage.get_page(link, session=self.session)   File "/usr/lib/python2.7/dist-packages/pip/index.py", line 757, in get_page     "Cache-Control": "max-age=600",   File "/usr/share/python-wheels/requests-2.9.1-py2.py3-none-any.whl/requests/sessions.py", line 480, in get     return self.request('GET', url, **kwargs)   File "/usr/lib/python2.7/dist-packages/pip/download.py", line 378, in request     return super(PipSession, self).request(method, url, *args, **kwargs)   File "/usr/share/python-wheels/requests-2.9.1-py2.py3-none-any.whl/requests/sessions.py", line 468, in request     resp = self.send(prep, **send_kwargs)   File "/usr/share/python-wheels/requests-2.9.1-py2.py3-none-any.whl/requests/sessions.py", line 597, in send     history = [resp for resp in gen] if allow_redirects else []   File "/usr/share/python-wheels/requests-2.9.1-py2.py3-none-any.whl/requests/sessions.py", line 195, in resolve_redirects     **adapter_kwargs   File "/usr/share/python-wheels/requests-2.9.1-py2.py3-none-any.whl/requests/sessions.py", line 576, in send     r = adapter.send(request, **kwargs)   File "/usr/share/python-wheels/CacheControl-0.11.5-py2.py3-none-any.whl/cachecontrol/adapter.py", line 46, in send     resp = super(CacheControlAdapter, self).send(request, **kw)   File "/usr/share/python-wheels/requests-2.9.1-py2.py3-none-any.whl/requests/adapters.py", line 376, in send     timeout=timeout   File "/usr/share/python-wheels/urllib3-1.13.1-py2.py3-none-any.whl/urllib3/connectionpool.py", line 610, in urlopen     _stacktrace=sys.exc_info()[2])   File "/usr/share/python-wheels/urllib3-1.13.1-py2.py3-none-any.whl/urllib3/util/retry.py", line 228, in increment     total -= 1 TypeError: unsupported operand type(s) for -=: 'Retry' and 'int'   My python version is the 2.7 and the pip is 8.1.1 How to move a file? How do I generate a random int value in a specific range? I have tried the following, but those do not work: Attempt 1: randomNum = minimum + (int)(Math.random() * maximum);  Bug: randomNum can be bigger than maximum. Attempt 2: Random rn = new Random(); int n = maximum - minimum + 1; int i = rn.nextInt() % n; randomNum =  minimum + i;  Bug: randomNum can be smaller than minimum. Midpoint-Convex and Continuous Implies Convex Given that $$f\left(\frac{x+y}{2}\right)\leqslant \frac{f(x)+f(y)}{2}~,$$ how can I show that $f$ is convex. Thanks.      Edit: I'm sorry for all the confusion. $f$ is assumed to be continuous on an interval $(a,b)$. I have a list of structs and I want to change one element. For example :  MyList.Add(new MyStruct("john"); MyList.Add(new MyStruct("peter");   Now I want to change one element:  MyList[1].Name = "bob"   However, whenever I try and do this I get the following error:     Cannot modify the return value of   System.Collections.Generic.List.this[int]‘ because it is not   a variable   If I use a list of classes, the problem doesn't occur.  I guess the answer has to do with structs being a value type.  So, if I have a list of structs should I treat them as read-only? If I need to change elements in a list then I should use classes and not structs? What to do when visa admission expires during lockdown? Good day. I'm not too sure how I should go about asking my question, so if it is in anyway confusing, feel free to edit it.   In my Group Theory course we defined and showed a few properties of the commutator subgroup $[G,G]$ of a group $G$. And then we stated and proved a lemma in lecture that I'm having some difficulty wrapping my head around. I'll state it here for clarity.  Lemma a) The commutator subgroup $[G,G]$ of $G$ is a normal subgroup of $G$. b) The quotient group $G / [G,G]$ is the largest abelian quotient of G in the sense that every homomorphism $\varphi : G \to A$ where $A$ is an an abelian group, induces a unique homomorphism $\bar \varphi : G/[G,G] \to A$ so that $\varphi =\bar \varphi \circ \pi$ where $\pi : G \to G/[G,G]$ is the quotient homomorphism.  Now, it's not the proof of this lemma that I'm having trouble with, it's the italicized text that is messing with me. I completely understand what it is that the italicized text is saying, I'm just not too sure why it is that the property gives us the "largeness" that is claimed. I can see that the above forces $G$ to "pass through" $G/[G,G]$ before it "reaches" $A$ (I apologize for the casual terminology), so I can sort of see why $G/[G,G]$ should be the largest quotient, in a non-rigorous sort of way.  Overall I'm very confused. Perhaps I'm missing something very simple. Any help or nudges in the right direction would be much appreciated.   As a side note I did try a search on Google and here on Stack Exchange and couldn't find anything that answered my question. So if I missed something obvious, then my apologies. Thank you in advance. The Ball From A Pass How do I make Panel always transparent like the Dock in GNOME 3? I'm using Ubuntu 17.10. I want the Panel to be always transparent instead of dynamic transparency. I have a question related to modeling short time-series. It is not a question , but how. What method would you recommend for modeling (very) short time-series (say of length $T \leq 20$)? By "best" I mean here the most robust one, that is the least prone to errors due the fact of limited numbers of observations. With short series single observations could influence the forecast, so the method should provide a cautious estimate of errors and possible variability connected to the forecast. I am generally interested in univariate time-series but it would be also interesting to know about other methods. How can I access and process nested objects, arrays or JSON?