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| bio | website | about:blank |
|---|---|---|
| location | Berlin, Germany | |
| age | 18 | |
| visits | member for | 2 years, 4 months |
| seen | 3 hours ago | |
| stats | profile views | 229 |
I'm a highschool student from Germany interested in functional programming, especially Haskell.
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Mar 5 |
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How to prove the equality $\sum_{j=0}^n (x)^j (-1)^{n-j} \left\{{n \atop j}\right\} = x^n$? Is your $(x)^j$ the same as $x^\overline{j}?$ |
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Mar 5 |
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Equality of polynomials: formal vs. functional @Harry Stern: Yes :) |
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Mar 5 |
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Equality of polynomials: formal vs. functional @Qiaochu Yuan $a_k, b_k \in \mathbb{C}$ |
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Mar 4 |
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Equality of polynomials: formal vs. functional Sorry, formulated the question wrong. |
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Mar 4 |
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Equality of polynomials: formal vs. functional @Jason DeVito: $a_k$ and $b_k$ are just coefficients. They're independent of $x$. |
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Feb 23 |
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Three non-coplanar lines in the 3D-space always have a fourth one that intersect them all? This proof is the easiest to understand for me. Thank you. |
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Feb 13 |
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Does the formula $\sqrt{ 1 + 24n }$ always yield prime? Uhhh... That's difficult. Thanks for this link. |
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Feb 12 |
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Does the formula $\sqrt{ 1 + 24n }$ always yield prime? Changed. I thought it's very difficult or impossible to find a prime generating function which only yields primes. Can you give me an example? |
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Feb 12 |
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How can I systematically find a solution to this problem? That was my approach before. With the reposity formula for geometric sequences, you can even find a closed form for even / odd $n$. But I considered it uggly, as it's unusable if you can't spot such pattern. |
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Feb 12 |
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How can I systematically find a solution to this problem? Has this method a specific name? |
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Feb 12 |
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How can I systematically find a solution to this problem? That's cool. Thank you very much. |
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Feb 12 |
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How can I systematically find a solution to this problem? I'm a bit confused - can you explain the exact procedure on my example equation? |
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Feb 12 |
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Three non-coplanar lines in the 3D-space always have a fourth one that intersect them all? Actually, this was not homework or something else. I thought about this in context of another problem and found out, that this can be false if the lines might be coplanar. But in this case I can't think of any reason why there should be no such fourth line. This is a good idea for a proof. I'm going to think about it. |
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Jan 2 |
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Suggest quicker method for finding rate percent per annum @Ross Millikan: You first have to trigger $\TeX$-Mode by a $, and finish it with another. $150\$$ becomes $150\$.$ |
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Jan 2 |
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Suggest quicker method for finding rate percent per annum @Debanjan Sorry. Was just a bit feeling like Hey, this guy want's us to solve his homework. |
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Jan 2 |
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On profit loss (II) No upvote because you tell him the final result. This is probably homework and should teach something. |
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Jan 2 |
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Solving $x$, $y$ and $z$ You can use $\TeX$ markup to beautify your equations by putting $-marks around them. |
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Jan 2 |
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How to find a closed form for a sum involving $\max(x,y)$ Thank you very much. After some thinking before going to sleep, I found out that I derived the wrong formula out of thee problem, so it's $\sum_{0\le y<k}\sum_{0\le x<k-y}k - 1 - x - y$ and can even be simplified to $\sum_{0\le y<k}\sum_{0\le x<k-y}y$ with some thinking about the problem. I was just afraid of the $\max(x,y),$ as I don't know how to find a solution for this. |
