English

A note on the triameter of graphs

Combinatorics 2025-07-29 v1

Abstract

In this note, we give answers to three questions from the paper [A. Das, Triameter of graphs, Discuss. Math. Graph Theory, 41 (2021), 601--616]. Namely, we obtain a tight lower bound for the triameter of trees in terms of order and number of leaves. We show that in a connected block graph any triametral triple of vertices contains a diametral pair and that any diametral pair of vertices can be extended to a triametral triple. We also present several open problems concerning the interplay between triametral triples, diametral pairs and peripheral vertices in median and distance-hereditary graphs.

Keywords

Cite

@article{arxiv.2103.10806,
  title  = {A note on the triameter of graphs},
  author = {Artem Hak and Sergiy Kozerenko and Bogdana Oliynyk},
  journal= {arXiv preprint arXiv:2103.10806},
  year   = {2025}
}
R2 v1 2026-06-24T00:21:17.160Z