English

The Interval function, Ptolemaic, distance hereditary, bridged graphs and axiomatic characterizations

Discrete Mathematics 2020-05-15 v1 Combinatorics

Abstract

In this paper we consider certain types of betweenness axioms on the interval function IGI_G of a connected graph GG. We characterize the class of graphs for which IGI_G satisfy these axioms. The class of graphs that we characterize include the important class of Ptolemaic graphs and some proper superclasses of Ptolemaic graphs: the distance hereditary graphs and the bridged graphs. We also provide axiomatic characterizations of the interval function of these classes of graphs using an arbitrary function known as \emph{transit function}.

Keywords

Cite

@article{arxiv.2005.06751,
  title  = {The Interval function, Ptolemaic, distance hereditary, bridged graphs and axiomatic characterizations},
  author = {Manoj Changat and Lekshmi Kamal K. Sheela and Prasanth G. Narasimha-Shenoi},
  journal= {arXiv preprint arXiv:2005.06751},
  year   = {2020}
}
R2 v1 2026-06-23T15:32:13.832Z