On the Planarity of Graphs Associated with Symmetric and Pseudo Symmetric Numerical Semigroups

Abstract

Let S(m,e) be a class of numerical semigroups with multiplicity m and embedding dimension e. We call a graph GS an S(m,e)-graph if there exists a numerical semigroup S∈S(m,e) with V(GS)={x:x∈g(S)} and E(GS)={xy⇔x+y∈S}, where g(S) denotes the gap set of S. The aim of this article is to discuss the planarity of S(m,e)-graphs for some cases where S is an irreducible numerical semigroup.

Keywords

• numerical semigroup
• Frobenius number
• genus
• clique number
• planarity