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Viewing Version 3 of 'Euclid's proof of the infinitude of primes'
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Title of object: Euclid's proof of the infinitude of primes
Canonical Name: ProofThatThereAreInfinitelyManyPrimes
Type: Proof

Created on: 2002-06-04 15:02:01
Modified on: 2004-03-23 05:00:43

Creator: mathwizard
Modifier: mathwizard
Author: mathwizard

Classification: msc:11A41

Revision comment (for changes between this and next version):

Changes for correction #6856 ('slight grammar error').

Preamble:

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Content:

If there was only a finite amount of primes then there would be some largest prime $p$. However $p!+1$ is not divisible by any number $1<n\leq p$, since $p!$ is, so $p!+1$ cannot be factored by the primes we already know, but every integer greater than one is divisible by at least one prime, so there must be some prime greater than $p$ by which $p!+1$ is divisible.