English

Density of Numerical sets associated to a Numerical semigroup

Combinatorics 2021-05-11 v3

Abstract

A numerical set is a co-finite subset of the natural numbers that contains zero. Its Frobenius number is the largest number in its complement. Each numerical set has an associated semigroup A(T)={tt+TT}A(T)=\{t\mid t+T\subseteq T\}, which has the same Frobenius number as TT. For a fixed Frobenius number ff there are 2f12^{f-1} numerical sets. It is known that there is a number γ\gamma close to 0.4840.484 such that the ratio of these numerical sets that are mapped to Nf={0}(f,)N_f=\{0\}\cup(f,\infty) is asymptotically γ\gamma. We identify a collection of families N(D,f)N(D,f) of numerical semigroups such that for a fixed DD the ratio of the 2f12^{f-1} numerical sets that are mapped to N(D,f)N(D,f) converges to a positive limit as ff goes to infinity. We denote the limit as γD\gamma_D, these constants sum up to 11 meaning that they asymptotically account for almost all numerical sets.

Keywords

Cite

@article{arxiv.1912.09355,
  title  = {Density of Numerical sets associated to a Numerical semigroup},
  author = {Deepesh Singhal and Yuxin Lin},
  journal= {arXiv preprint arXiv:1912.09355},
  year   = {2021}
}

Comments

13 pages,

R2 v1 2026-06-23T12:51:23.151Z