Abstract
Let G = (V,E) be a simple graph with vertex set V (G) = {v1,v2,...,vn} and edge set E(G). In this paper, first some sharp upper and lower bounds on the largest and least eigenvalues of graphs are given when vertices are removed. Some conjectures in (M. Aouchiche. Comparaison Automatisee d'Invariants en Theorie des Graphes. Ph.D. Thesis, ´ Polytechnique de Montreal, February 2006.) and (M. Aouchiche, G. Caporossi, and P. Hansen. Variable neighborhood search for extremal graphs, 20. Automated comparison of graph invariants. MATCH Commun. Math. Comput. Chem., 58:365-384, 2007.) involving the spectral radius, diameter and matching number are also proved. Furthermore, the extremal graph which attains the minimum least eigenvalue among all quasi-tree graphs is characterized.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.