Difference between revisions of "Prime number"

 
(merged Prime and Prime number articles and set the redirect)
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A '''prime number''' (or simply '''prime''') is a [[positive integer]] whose only positive [[divisor | divisors]] are 1 and itself.   
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A '''prime number''' (or simply '''prime''') is a positive [[integer]] <math>p>1</math> whose only positive [[divisor | divisors]] are 1 and itself.   
 
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Note that <math>1</math> is usually defined as being neither prime nor composite because it is its only factor among the [[natural number|natural numbers]].
  
 
== Advanced Definition ==
 
== Advanced Definition ==
 
When the need arises to include negative divisors, a '''prime''' is defined as an integer p whose only divisors are 1, -1, p, and -p.
 
When the need arises to include negative divisors, a '''prime''' is defined as an integer p whose only divisors are 1, -1, p, and -p.

Revision as of 16:31, 19 June 2006

A prime number (or simply prime) is a positive integer $p>1$ whose only positive divisors are 1 and itself. Note that $1$ is usually defined as being neither prime nor composite because it is its only factor among the natural numbers.

Advanced Definition

When the need arises to include negative divisors, a prime is defined as an integer p whose only divisors are 1, -1, p, and -p.