The set of all bijections from N to N is infinite, but not countable
Is symmetric group on natural numbers countable?
I read some articles, and seen some videos about a github project that do a sort of thing, but it's a little bit outdated things.I wanna see if this thing is possible to do, nowadays. Thanks How to write the Fibonacci Sequence? I had originally coded the program wrongly. Instead of returning the Fibonacci numbers between a range (ie. startNumber 1, endNumber 20 should = only those numbers between 1 &amp; 20), I have written for the program to display all Fibonacci numbers between a range (ie. startNumber 1, endNumber 20 displays = First 20 Fibonacci numbers). I thought I had a sure-fire code. I also do not see why this is happening.  startNumber = int(raw_input("Enter the start number here ")) endNumber = int(raw_input("Enter the end number here "))  def fib(n):     if n &lt; 2:         return n     return fib(n-2) + fib(n-1)  print map(fib, range(startNumber, endNumber))   Someone pointed out in my Part II (which was closed for being a duplicate - ) that I need to pass the startNumber and endNumber through a generator using a while loop. Can someone please point me in the direction on how to do this? Any help is welcome.    I'm a learning programmer and I've run into a bit of a jumble. I am asked to write a program that will compute and display Fibonacci's Sequence by a user inputted start number and end number (ie. startNumber = 20 endNumber = 100 and it will display only the numbers between that range). The trick is to use it inclusively (which I do not know how to do in Python? - I'm assuming this means to use an inclusive range?).  What I have so far is no actual coding but rather:   Write Fib sequence formula to infinite Display startNumber to endNumber only from Fib sequence.   I have no idea where to start and I am asking for ideas or insight into how to write this. I also have tried to write the Fib sequence forumla but I get lost on that as well. I need to find a way to import some .json models into Blender, and it seems I can't just import them the same way I can import a .obj model. So is there some way to convert a .json model to a .obj model, or another file type Blender can import? I've tried using Blockbench for this, but I think it only works with Minecraft recourse pack .json models, as those are the only models that will ever actually load in it. Thank you to anyone who can help me figure this out. If you run a code snippet, a hat still appears (hats are above snippets in the Z-order) Hi I'm solving some exercise problems in my text : "A Course in Mathematical Statistics".  I'm in the chapter "Point estimation" now, and I want to find a UMVUE of $\theta$ where $X_1 ,...,X_n$ are i.i.d random variables with the p.d.f $f(x; \theta)=\theta e^{-\theta x}, x\gt0$.   I know that $E(X_i)=1/\theta,$ for each $i$, and also have that $\bar{X}$ (or equivalently $\sum_1^n X_i$) is a complete sufficient statistic for $\theta$. But I cannot go any further here. Somebody can help me? I need to prove that $H$ is a maximal normal subgroup of $G$ if and only if $G/H$ is simple.  My proof to the $(\Rightarrow)$ direction seems too much trivial:  Let us assume there exist $A$ so that $A/H\lhd G/H$. Then by definion, $H$ must be normal in $A$. Because $H$ is maximal, we get $H=A$ and therefore $A/H={1}$  Is it correct?  Update:  Now I see that I need to prove that not only $A\lhd H$ but also $A\lhd G$. Assumig I have proven that, is the proof correct? Who fired the shot and what is the symbolism in firing shot right next to Lucas at the end of the movie? At the end of , during the deer hunt, there’s a shot fired right next to Lucas (deliberately missing the shot).   Who fired the shot? Is it Theo's son? What is the meaning of that scene? Is someone warning Lucas that he made a mistake and definitely, Lucas will be punished in the future? Let $E$ be an empty set. Then, $\sup(E) = -\infty$ and $\inf(E)=+\infty$. I thought it is only meaningful to talk about $\inf(E)$ and $\sup(E)$ if $E$ is non-empty and bounded?   Thank you. Binding energy and mass I’ve been told that a greater binding energy means the nucleus is more tightly bound, and therefore that decreases the mass of the nucleus with respect to its nucleons when separated. But why does a tighter nucleus mean a smaller mass? Integral of the square of the normal distribution. Does someone know what the integral of the square of the normal distribution with standard deviation sigma over the range $-\infty$ to $+\infty$ is?  Thanks! What changes after peer review but prior to final submission are acceptable for a conference paper? What is the life expectancy of a Wookiee? At lunch, my coworkers and I were discussing The Force Awakens, and started questioning Chewbacca's age.  A quick check of  and it says he is possibly about 230 years old as of Episode VII.  Following the  link on that page, Wookieepedia claims that they live to be 400 years old.  Do we know from canon what the average life expectancy of a Wookiee is? Unable to log in to Stack Exchange Are these adjectives interchangeable?  I always hear: 'An Arab man.' but never 'An Arabic man.' and I always hear 'Arabic coffee' but never hear 'Arab coffee.' $a_1x_1+a_2x_2+a_3x_3+...+a_nx_n=$ is called a linear equation because it represents the equation of a line in an n dimensional space. So "linear" comes from the word "line".Basically there should not be any higher power of x failing which the graph of the function will not be a straight line.  simillarly  $a(x)y+b(x)y'+c(x)y"+d(x)y'''+...+q(x)=0$ is also called linear differential equation because all the derivatives have power equal to 1 which is similar to the above definition of a linear equation.  A function f is called linear if: $f(x+y)=f(x)+f(y)$ and $f(cx)=cf(x)$. Here c is a constant. In this definition of linearity of function "$f$" what does the word linear means? How does it relate to a straight line?  Finally what does the term linear means in case of linear vector spaces? Where is the reference to a straight line?  So, whether linear is just a word used in different contexts? Does it have different meaning in different situation? Or linearity refers to some relation to a straight line? At Least please explain how the linearity of function f and linear vector space relate to the equation of a line. Gedit has a transparent background since upgrade to 16.10 Since I upgraded to from 16.04 to 16.10, gedit has strange new "feature": its background is totally transparent.    Where can this come from ?  Notice I'm using Unity and don't have any specific gnome package installed besides what comes by default. Notice also that in 16.04 I used the Vivacious theme from ravefinity PPA, but I had to go back to Ambiance as Vivacious was broken in 16.10. Maybe it's related.  [EDIT] changing the 'Fonts and Colors' in gedit to any theme other than default (Kate, Solarized, Oblivion, etc..) solves the issue. So there must be a faulty gtksourview file in my home somewhare, but I can't find it... How can standing waves be produced in an open organ pipe if the ends are open? How can standing waves be produced in an open organ pipe even though both of its ends are open? Can someone explain with more clarity? CS0120: An object reference is required for the nonstatic field, method, or property 'foo' How to check which package created a user? It is suspected that some packages have scripts run at install time which create user accounts in /etc/passwd. How can I check which package created a specific user? I'm going to install Linux on Lenovo B5400, which contains:   500GB Hybrid SSHD with a 8 GB SSD and 500 GB HDD   Designing partitions for my 2 Linux distros was quite easy before, when I had only HDD. I always had:   10GB for Linux distro (mounted as "/") 10GB for another distro (again "/"; for another distro; for testing purposes or to assure continuity when switching distros) 2GB for swap (used for both distros; no need to separate) 300GB+ for "/home" (used for both distros; different usernames eliminates possible conflicts)   It's simple, isn't it? I would like to keep this approach, but I know that SSD has its own specificity - it prefers to be read, continuous writing may affect its life span. I don't want to kill SSD in a year, so I would like to move some system partitions to HDD in order to protect SSD. As far as I know /tmp is one of often read&amp;written locations. How much space it needs? What else should be placed on HDD?  Or: how to design partitions to achieve exactly the same effect and to keep SSD as safe as possible?  I'd be grateful for your help.