English

Edge Intersection Graphs of Paths on a Triangular Grid

Discrete Mathematics 2022-03-09 v1 Data Structures and Algorithms

Abstract

We introduce a new class of intersection graphs, the edge intersection graphs of paths on a triangular grid, called EPGt graphs. We show similarities and differences from this new class to the well-known class of EPG graphs. A turn of a path at a grid point is called a bend. An EPGt representation in which every path has at most kk bends is called a Bk_k-EPGt representation and the corresponding graphs are called Bk_k-EPGt graphs. We provide examples of B2_{2}-EPG graphs that are B1_{1}-EPGt. We characterize the representation of cliques with three vertices and chordless 4-cycles in B1_{1}-EPGt representations. We also prove that B1_{1}-EPGt graphs have Strong Helly number 33. Furthermore, we prove that B1_{1}-EPGt graphs are 77-clique colorable.

Keywords

Cite

@article{arxiv.2203.04250,
  title  = {Edge Intersection Graphs of Paths on a Triangular Grid},
  author = {Vitor T. F. de Luca and María Pía Mazzoleni and Fabiano S. Oliveira and Tanilson D. Santos and Jayme L. Szwarcfiter},
  journal= {arXiv preprint arXiv:2203.04250},
  year   = {2022}
}

Comments

19 pages, 12 figures

R2 v1 2026-06-24T10:06:20.810Z