perfect number
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enMaths in a minute: Number mysteries
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<p>Number theory is famous for problems that everyone can understand and that are easy to express, but that are fiendishly difficult to prove. Here are some of our favourites.</p>
<h3>The Goldbach conjecture</h3>
<p>The Goldbach conjecture is named after the mathematician <a href="http://www-history.mcs.st-and.ac.uk/Biographies/Goldbach.html">Christian Goldbach</a> who formulated it in the middle of the eighteenth century. It states that any even natural number greater than 2 can be written as the sum of two prime numbers. </p><p><a href="http://plus.maths.org/content/maths-minute-number-mysteries" target="_blank">read more</a></p>http://plus.maths.org/content/maths-minute-number-mysteries#commentsGoldbach ConjectureMersenne primeMersenne searchnumber theoryperfect numberTue, 16 Jul 2013 08:49:15 +0000mf3445925 at http://plus.maths.org/content