The system of sets of lengths in Krull monoids under set addition
نویسندگان
چکیده
Let H be a Krull monoid with class group G and suppose that each class contains a prime divisor. Then every element a ∈ H has a factorization into irreducible elements, and the set L(a) of all possible factorization lengths for a is the set of lengths of a. We consider the system L(H) = {L(a) | a ∈ H} of all sets of lengths, and we characterize (in terms of the class group G) when L(H) is additively closed under set addition.
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