Almost Symmetric Numerical Semigroups Generated by Four Elements
نویسندگان
چکیده
In this paper, we study almost symmetric numerical semigroups generated by 4-elements. Rosales and Garćıa-Sánchez [RG2] proved that every almost symmetric numerical semigroup can be constructed by removing some minimal generators from an irreducible numerical semigroup with the same Frobenius number. Using this result, we concretely construct almost symmetric numerical semigroups generated by 4-elements from an irreducible numerical semigroup generated by 2 or 3-elements. In this situation, we prove that we have no almost symmetric numerical semigroups with embedding dimension 4 whose type is more than 3.
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