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Prime Numbers


Date: 9/20/95 at 17:51:59
From: Anonymous
Subject: Prime numbers

What are prime numbers?


Date: 9/21/95 at 22:13:56
From: Doctor Ken
Subject: Re: Prime numbers

Hello!

A prime number is a positive number that has exactly two factors, 1 and 
itself.  For example, if we list the factors of 28, we have 1, 2, 4, 7, 
14, and 28.  That's six factors.  If we list the factors of 29, we only
have 1 and 29.  That's 2.  So we say that 29 is a prime number, but 28 
isn't.  

Note that the definition of a prime number doesn't allow 1 to be a prime
number: 1 only has one factor, namely 1.  Prime numbers have EXACTLY two
factors, not "at most two" or anything like that.

Here are the first few prime numbers:
2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 
71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 
151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, etc.

-Doctor Ken,  The Geometry Forum
    
Associated Topics:
Elementary Prime Numbers

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