Book Description

In this dissertation, we study three recent generalizations of unique factorization; the almost Schreier property, the inside factorial property, and the IDPF property. Let R be an integral domain and let p be a nonzero element of R. Then, p is said to be almost primal if whenever p [vertical line] xy, there exists an integer k [greater than or equal to] 1 and p 1, p 2 [is an element of] R such that p k = p 1 p 2 with p 1 [vertical line] x k and p 2 [vertical line] y k . R is said to be almost Schreier if every nonzero element of R is almost primal. Given an M -graded domain R = [tensor product of modules] m [is an element of] M R m, where M is a torsion-free, commutative, cancellative monoid, we classify when R is almost Schreier under the assumption that R [is a subset of] R is a root extension. We then specialize to the case of commutative semigroup rings and show that if R [M] [is a subset of] [Special characters omitted.] is a root extension, then R [M] is almost Schreier if and only if R is an almost Schreier domain and M is an almost Schreier monoid.