Definition:Tidy Factorization

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Definition

Let $\struct {D, +, \circ}$ be an integral domain whose unity is $1_D$.

Let $\struct {U_D, \circ}$ be the group of units of $\struct {D, +, \circ}$.


Any factorization of $x \in D$ can always be tidied into the form:

$x = u \circ y_1 \circ y_2 \circ \cdots \circ y_n$

where $u \in \struct {U_D, \circ}$, and may be $1_D$, and $y_1, y_2, \ldots, y_n$ are all non-zero and non-units.


This is done by forming the ring product of all units of a factorization into one unit, and rearranging all the remaining factors as necessary.


Such a factorization is called tidy.


Examples

Tidy Factorizations of $6$

Two examples of tidy factorizations of $6$ in the set of integers $\Z$ are:

\(\ds 6\) \(=\) \(\ds 1 \times 2 \times 3\)
\(\ds 6\) \(=\) \(\ds \paren {-1} \paren {-3} \times 2\)


Linguistic Note

The spelling factorization is the US English version.

The UK English spelling is factorisation, but the tendency is for the literature to use the factorization form.


Sources