English

Quasi-polynomial growth of numerical and affine semigroups with constrained gaps

Combinatorics 2022-08-23 v1 Commutative Algebra Group Theory

Abstract

A common tool in the theory of numerical semigroups is to interpret a desired class of semigroups as the integer lattice points in a rational polyhedron in order to leverage computational and enumerative techniques from polyhedral geometry. Most arguments of this type make use of a parametrization of numerical semigroups with fixed multiplicity mm in terms of their mm-Ap\'{e}ry sets, giving a representation called Kunz coordinates which obey a collection of inequalities defining the Kunz polyhedron. In this work, we introduce a new class of polyhedra describing numerical semigroups in terms of a truncated addition table of their sporadic elements. Applying a classical theorem of Ehrhart to slices of these polyhedra, we prove that the number of numerical semigroups with nn sporadic elements and Frobenius number ff is polynomial up to periodicity, or quasi-polynomial, as a function of ff for fixed nn. We also generalize this approach to higher dimensions to demonstrate quasi-polynomial growth of the number of affine semigroups with a fixed number of elements, and all gaps, contained in an integer dilation of a fixed polytope.

Keywords

Cite

@article{arxiv.2208.09760,
  title  = {Quasi-polynomial growth of numerical and affine semigroups with constrained gaps},
  author = {Michael DiPasquale and Bryan R. Gillespie and Chris Peterson},
  journal= {arXiv preprint arXiv:2208.09760},
  year   = {2022}
}

Comments

15 pages