Abstract. An integral domain R is a finite factorization domain if each nonzero element of R has only finitely many divisors, up to associates. We show that a Noetherian domain R is an FFD ⇔ for each overring R of R that is a finitely generated R-module, U (R )/U (R) is finite. For R local this is also equivalent to each R/[R : R ] being finite. We show that a one-dimensional local domain (R, M ) is an FFD ⇔ either R/M is finite or R is a DVR.In their study of factorization [2], the first author, D.F. Anderson, and M. Zafrullah introduced the notion of a finite factorization domain (FFD). An integral domain R is an FFD if every nonzero element of R has only a finite number of nonassociate divisors. The three authors continued their investigation of FFD's in [3], and F. Halter-Koch studied FFD's and their monoid analog in [9]. Earlier, A. Grams and H. Warner [8] introduced the related concept of idf-domains. An integral domain R is an idf-domain (for irreducible-divisor-finite) if each nonzero element of R has only finitely many nonassociate irreducible divisors.We adopt the following definitions and notation. For an integral domain R with quotient field K, U (R) is the group of units of R and G(R) = K * /U (R), partially ordered by aU (R) ≤ bU (R) ⇔ a|b in R, is the group of divisibility of R. Clearly G(R) is order-isomorphic to the group Prin(R) of nonzero principal fractional ideals of R ordered by reverse inclusion. We sometimes call an irreducible element of an integral domain an atom and an integral domain R is said to be atomic if every nonzero, nonunit element of R is a finite product of atoms. For an integral domain R, R * = R − {0} andR is the integral closure of R. For a survey of factorization in integral domains, the reader is referred to [2][3] and for standard definitions and results from commutative ring theory to [6] and [11].We begin by giving several equivalent conditions for an integral domain to be an FFD.
Theorem 1. For an integral domain R, the following conditions are equivalent:(1) R is an FFD, (2) every nonzero (principal ) ideal of R is contained in only finitely many principal ideals, (3) for each x ∈ G(R) with x ≥ 0, the interval [0, x] is finite, (4) for any infinite collection of distinct principal ideals {(r α )} of R, α (r α ) = 0,