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How to Remove URLs from Google Search Engine I have used so many things like url removal request and deleted the pages etc., but still the errors are shown in my webmaster tools.  How can I remove the urls completely from Google? How should a bot earn enough reputation to perform the actions necessary for that bot? How to cluster time series? I have a question about cluster analysis. There are 3000 companies, which have to be clustered according to their power usage over 5 years. Each company has values for every hour during 5 years. I would like to find out if some companies have the same pattern in usage power over the time period. The results should be used for daily prediction of power usage. If you have some ideas how to cluster time series in SPSS, please share with me. Series convergence or divergence how to test I have the following series defined.   $$\displaystyle\sum_{k=1}^{n} \cos \left( {\frac{\pi}{2}} k \right) \frac{k}{k+1000} \frac{1}{\sqrt{k}}$$ where $n = 1,2...$  How to test whether this series converges or diverges ? I am designing a poster, which has some geometrical shapes (TikZ paths) surrounded by some text. I would like the text to flow neatly around these shapes. I bet there's some clever TikZ magic that could do this.  EDIT: This is the sort of effect I want, sorry to not be clear:    \documentclass[a4paper]{article} \usepackage{tikz} \begin{document} \begin{tikzpicture} \draw (0,0) to (2,-2) to (2,-4) to (4,-4) to [out=up, in=down] (6.5,0); \node [text width=6cm, anchor=north west] at (0,0) { \hspace{5pt}  This is the sort of effect I want to \\ \hspace{23pt} achieve, with text automatically \\ \hspace{36pt} constrained by some \\ \hspace{46pt} geometrical form. Here \\ \hspace{55pt} it's just a curve, \\ \hspace{57pt} but this could \\ \hspace{57pt} also be the \\ \hspace{57pt} text label \\ \hspace{57pt} of a node.}; \end{tikzpicture} \end{document} How to install the latest Arduino IDE? javascript document.getElementsByClassName compatibility with IE Coin sequence paradox from Martin Gardner's book Object-orientation in C What would be a set of nifty preprocessor hacks (ANSI C89/ISO C90 compatible) which enable some kind of ugly (but usable) object-orientation in C?  I am familiar with a few different object-oriented languages, so please don't respond with answers like "Learn C++!". I have read "" (beware: PDF format) and several other interesting solutions, but I'm mostly interested in yours :-)!    See also How to justify the definition of summation $s_n=\sum_{i=1}^n a_i=a_1+\cdots+a_n$? I read  and found that they define summation via recursion, so I decided to formalize the proof that that this definition is actually valid. I've two questions:   Does my proof contain any error? Are there other simple ways to define summation?   Thank you so much!     Suppose that $(a_1,\cdots,a_n)$ is a finite sequence in $\mathbb N$. Show that there is a sequence $(s_1,\cdots,s_n)$ such that $s_1=a_1$ and $s_{i+1}=s_i+a_{i+1}$ for all $1\leq i&lt;n$.   My attempt:  We define mapping $f$ as follows: $f: \mathbb N\times\mathbb N\to\mathbb N\times\mathbb N: (i,a)\mapsto\begin{cases} (i+1,a+a_{i+1})&amp;\text{if }i&lt;n\\ (i+1,a)&amp;\text{if }i\geq n \end{cases}$  By recursion theorem, there is a unique sequence $(p_i\mid i\in\mathbb N)$ such that $p_0=(1,a_1)$ and $p_{i+1}=f(p_i)$. Let $\pi:\mathbb N\times\mathbb N\to\mathbb N$ be the projection to the second co-ordinate i.e. $\pi(i,a)=a$. Let $s_i=\pi(p_i)$ for all $1\leq i\leq n$, then $(s_i\mid 1\leq i\leq n)$ is the required sequence. It's clear from the definition of $s_i$ that $s_{i+1}=s_i+a_{i+1}$ for all $1\leq i&lt;n$. Suppose $A,B,C$ are sets. Prove that $A\mathbin\triangle B\subseteq C \iff A\cup C=B\cup C$. Suppose $A,B,C$ are sets.  Prove that $A\mathbin\triangle B\subseteq C \iff A\cup C=B\cup C$.  I proved that for $x\in A\setminus B$, $x\in A\cup C$ and for $x\in B\setminus A$, $x\in B\cup C$. How do I show that $A\cup C=B\cup C$, and that $A\mathbin\triangle B\subseteq C \iff A\cup C=B\cup C$? What should the order of DNS servers be for an AD Domain Controller and Why? This is a  about Active Directory DNS Settings. Related:     Assuming an environment with multiple domain controllers (assume that they all run DNS as well):  in what order should the DNS servers be listed in the network adapters for each domain controller? Should 127.0.0.1 be used as the primary DNS server for each domain controller? Does it make any difference, if so what versions are affected and how? $S^2 \times S^2$ is diffeomophic to $G_2(\mathbb{R}^4)$ $G_2(\mathbb{R}^4)$ is the Grassmannian manifold of two-dimensional subspaces of $\mathbb{R}^4$. I would like a detailed proof. Can it be done explicitly? I mean, showing the map and checking its differentiability using charts? I am very new to LaTeX and I am writing my thesis. In a chapter, I want to show my codes, which are in Mathematica.   I use the listings package as follows:  \documentclass{article}   \usepackage{listings}   \begin{document}   \lstset{language=Mathematica}    \begin{lstlisting}   Do[i^j,{i,1,10},{j,1,10}]   \end{lstlisting}    \end{document}   However, the output is much different to what the code looks like in the Mathematica IDE (even if I use other languages in \lstset{language=&lt;name&gt;}):    I read some questions on the site but, in some of them, the font or color of the codes were not the same. Could you please help me to display something like the picture below in LaTeX?  If it is important, I am using the BiDi package. Possible Duplicate:          Can anyone offer me advice on how to clean my camera's sensor?   Should I do this myself, or take the camera to a professional? Is it precarious, or easy with the right amount of care?   I have a Nikon D3000 that has a small dot off-center of the sensor. I believe it is dirt, and I would like to remove it. I'm tempted to use a cotton-bud, but I'm afraid that I might damage the sensor.  The dot appeared after a trip to a tropical area where the camera became wet. I took the lens off and a lot of moisture, and possibly some dirt, went into the camera. The lens became fogged-up.  When I returned from my trip I ran a hair dryer for (air only, without heat) 10 minutes through the battery compartment, believing this would circulate around and dry the camera. Consequently, I noticed many speckled dots around the sensor. I also believe there's a subtle but persistent haze when I look through the lens, but I could be wrong.  It's worth noting that the photos are fine, with no evidence of distortion or blurring. The camera is now dry and it's been months since this happened. But the dot on the sensor has been there since, like an itch I can't rub. How can I determine whether my processor is 32-bit or 64-bit? My processor is AMD Phenom 8450 triple-core. Adaline is 100-something years old, and her daughter appears to be 90 years old. Well, Adaline gave birth to her in her mid 20's, and to be precise, she should be 80.   Anyways, Adaline's old lover's son (Ellis) is probably in his late 20's/early 30's. And Adaline has stopped aging at 29, which is pretty close to Ellis. Her old lover is said to be a few years younger than her and still, his son is so young. Also, Adaline could make him believe that she is the daughter of her own old self.   Then,      how can Adaline's real life daughter be so old?   I can't make sense out of this.  Why is it this way? The age pattern of the actors and actresses is inconsistent. It seems to me that the filmmakers have exaggerated some things. Assume the continuum hypothesis is false, and add that as an axiom to ZF set theory. How many cardinalities are between the rationals and the reals in this case? Only one? Infinitely many? Countably many? Uncountably many? What are the possibilities to the quantity of counterexamples? probability that there is at least one defective part I study economics and I am trying to solve this problem - without success, unfortunately.     A machine has a defect rate of 6%.       a) Chosen at random 4 pieces (with replacement) from the production flow, compute the probability that none is defective.   b) In the event that extractions are performed 60, compute the probability that there is at least one defective part.   I have no idea how to answer the first question. What logical processes can I use?  Regarding the second question, I thought of using the binomial random variable with $n = 60$ and $p = 0.06$. Then:  $$\begin{multline} P (X \geq 1) = 1 - P (X &lt; 1) = 1 - P (X = 0) = \\ = 1 - \binom{60}{0}  \cdot (0.06)^ 0 \cdot (0.94)^{60} = 1 - 0.02446 = 0.97558.\end{multline}$$  Can somebody please explain me how to solve this problem? Thank you very much. Which is faster/best? SELECT * or SELECT column1, colum2, column3, etc I've heard that SELECT * is generally bad practice to use when writing SQL commands because it is more efficient to SELECT columns you specifically need.  If I need to SELECT every column in a table, should I use   SELECT * FROM TABLE   or   SELECT column1, colum2, column3, etc. FROM TABLE   Does the efficiency really matter in this case? I'd think SELECT * would be more optimal internally if you really need all of the data, but I'm saying this with no real understanding of database.  I'm curious to know what the best practice is in this case.  UPDATE: I probably should specify that the only situation where I would really want to do a SELECT * is when I'm selecting data from one table where I know all columns will always need to be retrieved, even when new columns are added.   Given the responses I've seen however, this still seems like a bad idea and SELECT * should never be used for a lot more technical reasons that I ever though about.