Factorization | Ring theory | Algebraic number theory

Unique factorization domain

In mathematics, a unique factorization domain (UFD) (also sometimes called a factorial ring following the terminology of Bourbaki) is a ring in which a statement analogous to the fundamental theorem of arithmetic holds. Specifically, a UFD is an integral domain (a nontrivial commutative ring in which the product of any two non-zero elements is non-zero) in which every non-zero non-unit element can be written as a product of prime elements (or irreducible elements), uniquely up to order and units. Important examples of UFDs are the integers and polynomial rings in one or more variables with coefficients coming from the integers or from a field. Unique factorization domains appear in the following chain of class inclusions: rngs ⊃ rings ⊃ commutative rings ⊃ integral domains ⊃ integrally closed domains ⊃ GCD domains ⊃ ⊃ principal ideal domains ⊃ Euclidean domains ⊃ fields ⊃ algebraically closed fields (Wikipedia).

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Rings and modules 5 Examples of unique factorizations

This lecture is part of an online course on rings and modules. We give some examles to illustrate unique factorization. We use the fact that the Gaussian integers have unique factorization to prove Fermat's theorem about primes that are sums o 2 squares. Then we discuss a few other quadra

From playlist Rings and modules

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Abstract Algebra | Introduction to Unique Factorization Domains

We introduce the notion of a unique factorization domain (UFD), give some examples and non-examples, and prove some basic results. Integral Domain Playlist: https://www.youtube.com/playlist?list=PL22w63XsKjqxPO6pQ8wiZcIrtpTznGSre Please Subscribe: https://www.youtube.com/michaelpennmath?

From playlist Abstract Algebra

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Rings and modules 4 Unique factorization

This lecture is part of an online course on rings and modules. We discuss unique factorization in rings, showing the implications (Integers) implies (Euclidean domain) implies (Principal ideal domain) implies (Unique factorization domain). We give a few examples to illustrate these implic

From playlist Rings and modules

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Unique factorization and its difficulties I Data Structures in Mathematics Math Foundations 198

The Unique Factorization Theorem is also called the Fundamental Theorem of Arithmetic: the existence and uniqueness of a prime factorization for a natural number n. It is a pillar of number theory, and goes back to Euclid. We want to have a look at the logical structure of this theorem.

From playlist Math Foundations

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Unique factorization and its difficulties II | Data Structures Math Foundations 199

We continue with our discussion of the Fundamental Theorem of Arithmetic, which is that any natural number is uniquely factorizable in to primes. But this is not exactly true, at least not if we allow such big numbers as z into our realm of natural numbers! In this video we look at the ac

From playlist Math Foundations

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Abstract Algebra | If D is a UFD then D[x] is a UFD.

We prove an important result that states the ring of polynomials whose coefficients are from a unique factorization domain is itself a unique factorization domain. Along the way, we define the content of a polynomial, prove Gauss' lemma, and prove that if a polynomial factors over the fiel

From playlist Abstract Algebra

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RIngs 15 Polynomials

This lecture is part of an online course on rings and modules. We review basic properties of polynomials over a field, and show that polynomials in any number of variables over a field or the integers have unique factorization. For the other lectures in the course see https://www.youtu

From playlist Rings and modules

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Simplifying a factorial divided by another factorial

👉 Learn all about factorials. Factorials are the multiplication of a number in descending integer values back to one. Factorials are used often in sequences, series, permutations, and combinations. Factorial quotient expressions are simplified by canceling out common integer products or

From playlist Sequences

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What is a factorial

👉 Learn all about factorials. Factorials are the multiplication of a number in descending integer values back to one. Factorials are used often in sequences, series, permutations, and combinations. Factorial quotient expressions are simplified by canceling out common integer products or

From playlist Sequences

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Dedekind domains: Introduction

This lecture is part of an online graduate course on commutative algebra, and is an introduction to Dedekind domains. We define Dedekind domains, and give several examples of rings that are or are not Dedekind domains. This is a replacement video: as several alert viewers pointed out, t

From playlist Commutative algebra

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Commutative algebra 9 (Euclidean domains)

This lecture is part of an online course on commutative algebra, following the book "Commutative algebra with a view toward algebraic geometry" by David Eisenbud. We describe one method of visualizing rings by drawing pictures of their points, and use this to show that the ring of Gaussia

From playlist Commutative algebra

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Commutative algebra 10 (Weierstrass preparation theorem)

This lecture is part of an online course on commutative algebra, following the book "Commutative algebra with a view toward algebraic geometry" by David Eisenbud. In this lecture we describe a second method of visualizing rings by drawing a point for each basis element of the ring. We giv

From playlist Commutative algebra

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Visual Group Theory: Lecture 7.4: Divisibility and factorization

Visual Group Theory: Lecture 7.4: Divisibility and factorization The ring of integers have a number of properties that we take for granted: every number can be factored uniquely into primes, and all pairs of numbers have a unique gcd and lcm. In this lecture, we investigate when this happ

From playlist Visual Group Theory

Related pages

Square-free integer | Prime ideal | Integral domain | Schreier domain | Formal power series | Subclass (set theory) | Subring | Zero ring | Regular local ring | Ring of integers | GCD domain | Auslander–Buchsbaum theorem | Homogeneous polynomial | Empty product | Atomic domain | Entire function | Greatest common divisor | Principal ideal domain | Polynomial ring | Zariski ring | Projective module | Irreducible element | Dedekind domain | Gaussian integer | Monic polynomial | Mathematics | Unit (ring theory) | Field (mathematics) | Fundamental theorem of arithmetic | Noncommutative unique factorization domain | Divisor | Noetherian ring | Parafactorial local ring | Prime element | Ring (mathematics) | Eisenstein integer | Sphere | Euclidean domain | Integrally closed domain | Least common multiple | Ascending chain condition on principal ideals | Nicolas Bourbaki | Heegner number | Algebraic integer | Ideal class group | Commutative ring