visual sieve
http://plus.maths.org/content/taxonomy/term/846
enCatching primes
http://plus.maths.org/content/catching-primes
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Abigail Kirk </div>
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The primes are the building blocks of our number system, but there's no general formula that will give you all of them. If you want them, you have to hunt them down one by one. <b>Abigail Kirk</b> investigates a method that does just that. </div>
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<div class="pub_date">June 2008</div>
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<p>Prime numbers play a hugely important role as the fundamental building blocks of our number system — and they remain at the centre of some of the biggest mysteries of mathematics. Prime numbers are those whole numbers that can only be divided by themselves and the number 1. For example, 7 is a prime, but 6 is not, because 6 = 2 × 3. Non-primes are known as <i>composite numbers</i></p><p><a href="http://plus.maths.org/content/catching-primes" target="_blank">read more</a></p>http://plus.maths.org/content/catching-primes#comments47number theoryprime numberprime number searchvisual sieveSat, 31 May 2008 23:00:00 +0000plusadmin2331 at http://plus.maths.org/content