English

Diameter and connectivity of finite simple graphs

Combinatorics 2021-03-29 v1 Commutative Algebra

Abstract

Let GG be a finite simple non-complete connected graph on {1,,n}\{1, \ldots, n\} and κ(G)1\kappa(G) \geq 1 its vertex connectivity. Let f(G)f(G) denote the number of free vertices of GG and diam(G)\mathrm{diam}(G) the diameter of GG. Being motivated by the computation of the depth of the binomial edge ideal of GG, the possible sequences (n,q,f,d)(n, q, f, d) of integers for which there is a finite simple non-complete connected graph GG on {1,,n}\{1, \ldots, n\} with q=κ(G),f=f(G),d=diam(G)q = \kappa(G), f = f(G), d = \mathrm{diam}(G) satisfying f+d=n+2qf + d = n + 2 - q will be determined. Furthermore, finite simple non-complete connected graphs GG on {1,,n}\{1, \ldots, n\} satisfying f(G)+diam(G)=n+2κ(G)f(G) + \mathrm{diam}(G) = n + 2 - \kappa(G) will be classified.

Keywords

Cite

@article{arxiv.2103.14260,
  title  = {Diameter and connectivity of finite simple graphs},
  author = {Takayuki Hibi and Sara Saeedi Madani},
  journal= {arXiv preprint arXiv:2103.14260},
  year   = {2021}
}

Comments

10 pages, 8 figures