User alexandru moșoi - MathOverflow most recent 30 from http://mathoverflow.net 2013-05-21T09:20:43Z http://mathoverflow.net/feeds/user/507 http://www.creativecommons.org/licenses/by-nc/2.5/rdf http://mathoverflow.net/questions/14062/how-to-factorize-xn-1-in-z-pz How to factorize X^n - 1 in Z/pZ? Alexandru Moșoi 2010-02-03T22:05:34Z 2010-02-28T08:53:34Z <p>How do I factorize a polynomial \$X^n - 1\$ over <code>\$\mathbb{F}_p\$</code>? In particular I need to find factors of the polynomial \$X^{3^3 - 1} - 1 = X^{26} - 1\$ over \$\mathbb{F}_3\$.</p> http://mathoverflow.net/questions/7901/chances-to-win-an-election Chances to win an election Alexandru Moșoi 2009-12-05T21:32:08Z 2009-12-06T00:17:54Z <p>Let's say that tomorrow national president election is held. A poll asks 1100 persons which of the two candidates, A or B, will he or she will vote. 750 say will vote A, and 250 say will vote B. What are the chances each will win the election? I think this problem is not the same as choosing a random voter and let him or her decide. Therefore, I assume that the chance A wins elections is higher than 0.75, and closer to 1.</p> <p><strong>Update:</strong> Since the election generated a lot of fuss let me rephrase the question: you have a box containing \$N\$ white and black balls. From the box you extract \$N' &lt;= N\$ random balls and count \$W\$ white balls and \$B\$ black balls (\$W + B = N'\$). What is the probability that the box initially contained more white balls than black balls?</p> http://mathoverflow.net/questions/5386/typo-grammar-checker-for-latex/7055#7055 Answer by Alexandru Moșoi for Typo/grammar checker for LaTeX Alexandru Moșoi 2009-11-28T15:32:59Z 2009-11-28T15:32:59Z <p>I write latex in <a href="http://www.vim.org/" rel="nofollow">vim</a>. Latest versions have a built-in spell checker.</p> <pre><code>:set spell </code></pre> http://mathoverflow.net/questions/6833/difference-between-connected-vs-strongly-connected-vs-complete-graphs/6837#6837 Answer by Alexandru Moșoi for Difference between connected vs strongly connected vs complete graphs Alexandru Moșoi 2009-11-25T20:11:12Z 2009-11-25T20:11:12Z <ul> <li><em>Connected</em> is usually associated with undirected graphs (two way edges): there is a <strong>path</strong> between every two nodes.</li> <li><em>Strongly connected</em> is usually associated with directed graphs (one way edges): there is a <strong>route</strong> between every two nodes.</li> <li><em>Complete graphs</em> are undirected graphs where there is an <strong>edge</strong> between every pair of nodes.</li> </ul> http://mathoverflow.net/questions/870/symmetric-h-bases-for-postage-stamp-problem symmetric h-bases for postage stamp problem Alexandru Moșoi 2009-10-17T13:19:05Z 2009-11-20T21:56:16Z <p>I've been looking over a <a href="http://www.emis.de/journals/JIS/VOL12/Robinson/robinson4.ps" rel="nofollow" title="Some Postage Stamp 2-bases">paper</a> on Global Postage Stamp Problem (GPSP) with 2 stamps (h = 2). I understand how to build extremal symmetric basis, but I don't understand how to generalize to h'-bases for h' > 2: ie. compute the h'-range without resorting to Local Postage Stamp Problem.</p> http://mathoverflow.net/questions/14062/how-to-factorize-xn-1-in-z-pz/14156#14156 Comment by Alexandru Moșoi Alexandru Moșoi 2010-02-10T23:49:36Z 2010-02-10T23:49:36Z I tried countless variations on wolframalpha, but not &quot;factor x^26-1&quot;. thank you http://mathoverflow.net/questions/14062/how-to-factorize-xn-1-in-z-pz/14068#14068 Comment by Alexandru Moșoi Alexandru Moșoi 2010-02-03T22:34:34Z 2010-02-03T22:34:34Z Yes, it's part of a homework, but the factorization is already given at <a href="http://www.few.vu.nl/~jeu/Teaching/CC/Notes0.pdf" rel="nofollow">few.vu.nl/~jeu/Teaching/CC/Notes0.pdf</a> (page 22). Unfortunately the provided factorization is wrong and I need the correct one to continue. http://mathoverflow.net/questions/7901/chances-to-win-an-election/7919#7919 Comment by Alexandru Moșoi Alexandru Moșoi 2009-12-05T23:20:46Z 2009-12-05T23:20:46Z I scanned the article and it seems to discuss the polls, rather then the outcome based on an ideal poll. http://mathoverflow.net/questions/7901/chances-to-win-an-election/7909#7909 Comment by Alexandru Moșoi Alexandru Moșoi 2009-12-05T22:49:51Z 2009-12-05T22:49:51Z Yes, last 100 didn't respond. http://mathoverflow.net/questions/7901/chances-to-win-an-election Comment by Alexandru Moșoi Alexandru Moșoi 2009-12-05T22:04:00Z 2009-12-05T22:04:00Z You may assume any simplification you want. http://mathoverflow.net/questions/7901/chances-to-win-an-election Comment by Alexandru Moșoi Alexandru Moșoi 2009-12-05T22:01:00Z 2009-12-05T22:01:00Z Assume that the people won't lie to the pollster and they won't change their mind. http://mathoverflow.net/questions/7901/chances-to-win-an-election Comment by Alexandru Moșoi Alexandru Moșoi 2009-12-05T21:49:48Z 2009-12-05T21:49:48Z Real case: in Romania the president will be elected tomorrow. Polls say 54% voters will choses one candidate and 46% for the other. I wouldn't simply say that first candidate will win. http://mathoverflow.net/questions/870/symmetric-h-bases-for-postage-stamp-problem Comment by Alexandru Moșoi Alexandru Moșoi 2009-11-24T00:00:52Z 2009-11-24T00:00:52Z I provided a link to a paper which describes most of the terms.