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David Radcliffe
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David Radcliffe

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This is a directed graph with 1000 vertices, numbered from 0 to 999, and a directed edge from vertex n to vertex (n*n+2) mod 1000 for each n. I think it's rather pretty.
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Ah, that's explains the HT on your tweet.
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Definitely not.
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I wanted to share my Javascript application for searching for topological spaces. It's based on the tables from "Counterexamples in Topology" by Steen and Seebach.  I've been thinking about allowing users to add new topological spaces and properties to the database, but I'm not sure of the best way to manage this.
Topology Assistant. When you click on the name of a topological property, the cell background will change colors. If the background is light green, then the page will display topological spaces that have the given property. If the background is light pink, then the spaces that lack this property ...
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is this based purely on javascript?
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Using Python to see how the Times writes about men and women. Neal Caren - University of North Carolina, Chapel Hill mail web twitter scholar. Do men and women come up in different contexts in the newspaper? One quick way to answer that question is to compare the words in sentences that discuss ...
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What can we say about the patterns of leading digits of (2^n, 3^n, ..., 9^n)? My answer is here.
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I have a piece on Yitang Zhang's proof of bounded gaps and the notion of prime numbers as random numbers in Slate today: 
http://www.slate.com/articles/health_and_science/do_the_math/2013/05/yitang_zhang_twin_primes_conjecture_a_huge_discovery_about_prime_numbers.single.html
Last week, Yitang “Tom” Zhang, a popular math professor at the University of New Hampshire, stunned the world of pure mathematics when he announced that he had proven the “bounded gaps” conjecture about the distribution of prime numbers—a crucial milestone on the way to the even more elusive twin primes...
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Busy day in analytic number theory; Harald Helfgott has complemented his previous paper http://arxiv.org/abs/1205.5252 (obtaining minor arc estimates for the odd Goldbach problem) with major arc estimates, thus finally obtaining an unconditional proof of the odd Goldbach conjecture that every odd number greater than five is the sum of three primes.  (This improves upon a result of mine from last year http://terrytao.wordpress.com/2012/02/01/every-odd-integer-larger-than-1-is-the-sum-of-at-most-five-primes/ showing that such numbers are the sum of five or fewer primes, though at the cost of a significantly lengthier argument.) As with virtually all successful partial results on the Goldbach problem, the argument proceeds by the Hardy-Littlewood-Vinogradov circle method; the challenge is to make all the estimates completely effective and to optimise all parameters (which, among other things, requires a certain amount of computer-assisted computation).
Abstract: The ternary Goldbach conjecture, or three-primes problem, asserts that every odd integer N greater than 5 is the sum of three primes. The present paper proves this conjecture. Both the ternary Goldbach conjecture and the binary, or strong, Goldbach conjecture had their origin in an ...
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I am a college math instructor living in St. Paul MN. I am not a vice president at Google; that is a different David Radcliffe. I did not star in the Harry Potter movies; that is Daniel Radcliffe.
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