English

The shape of a random numerical semigroup

Combinatorics 2026-04-30 v1

Abstract

We study statistical properties of random numerical semigroups of a given genus. We analyze the graph of a typical numerical semigroup, understood as a function from N\mathbb{N} to N\mathbb{N}. If SS is a numerical semigroup of genus gg, this leads us to consider the collection of points (k1g1,ak(S)g)\left(\frac{k-1}{g-1},\frac{a_k(S)}{g} \right) where 1kg1 \le k \le g and ak(S)a_k(S) denotes the kkth smallest nonzero element of SS. We show that as gg \rightarrow \infty, this set of points typically becomes closer to a union of two line segments. We prove analogous results for numerical semigroups ordered by Frobenius number.

Keywords

Cite

@article{arxiv.2604.26127,
  title  = {The shape of a random numerical semigroup},
  author = {Maria Bras-Amorós and Nathan Kaplan and Deepesh Singhal},
  journal= {arXiv preprint arXiv:2604.26127},
  year   = {2026}
}

Comments

39 pages

R2 v1 2026-07-01T12:40:12.241Z