Prime NumbersDate: 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 |
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