STAR OPERATIONS ON KUNZ DOMAINS

Abstract

We study star operations on Kunz domains, a class of analyti-

cally irreducible, residually rational domains associated to pseudo-symmetric

numerical semigroups, and we use them to refute a conjecture of Houston, Mi-

mouni and Park. We also nd an estimate for the number of star operations

in a particular case, and a precise counting in a sub-case.

Keywords

• Star operation,pseudo-symmetric semigroup,Kunz domain,star regular domain

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