primal element
An element in a commutative ring is called primal if whenever , with , then thereexist elements such that
- 1.
,
- 2.
and .
Lemma. In a commutative ring, an element that is both irreducible and primal is a prime element
.
Proof.
Suppose is irreducible and primal, and . Since is primal, there is such that , with and . Since is irreducible, either or is a unit. If is a unit, with as its inverse, then , so that . But , we have that .∎