UFD
An integral domain satisfying
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Every nonzero element of that is not a unit can be factored into a product of a finite number of irreducibles,
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If and are two factorizations of the same element into irreducibles, then and we can reorder the ’s in a way that is an associate element of for all
is called a unique factorization domain (UFD), also a factorial ring.
The factors are called the prime factors of .
Some of the classic results about UFDs:
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On a UFD, the concept of prime element and irreducible element coincide.
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If is a field, then is a UFD.
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If is a UFD, then (the ring of polynomials on the variable over ) is also a UFD.
Since , these results can be extended to rings of polynomials with a finite number of variables.
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If is a principal ideal domain, then it is also a UFD.
The converse is, however, not true. Let a field and consider the UFD . Let the ideal consisting of all the elements of whose constant term is . Then it can be proved that is not a principal ideal. Therefore not every UFD is a PID.
Title | UFD |
Canonical name | UFD |
Date of creation | 2013-03-22 11:56:22 |
Last modified on | 2013-03-22 11:56:22 |
Owner | drini (3) |
Last modified by | drini (3) |
Numerical id | 19 |
Author | drini (3) |
Entry type | Definition |
Classification | msc 13G05 |
Synonym | unique factorization domain |
Related topic | IntegralDomain |
Related topic | Irreducible |
Related topic | EuclideanRing |
Related topic | EuclideanValuation |
Related topic | ProofThatAnEuclideanDomainIsAPID |
Related topic | WhyEuclideanDomains |
Related topic | Y2X32 |
Related topic | PID |
Related topic | PIDsAreUFDs |
Related topic | FundamentalTheoremOfArithmetic |
Defines | factorial ring |
Defines | prime factor |
Defines | UFD |
Defines | unique factorization |