Abstract

In this paper, we give a generalization of the author's previous result about real rootedness of clique polynomials of connected $K_{4}$-free chordal graphs to the class of $2$-connected $K_{5}$-free chordal graphs. The main idea is based on the graph-theoretical interpretation of the second derivative of clique polynomials. Finally, we conclude the paper with several interesting open questions and conjectures.

Highlights

  • Polynomials with only real roots are appeared in many branches of theoretical and applied mathematical sciences

  • The main idea is based on the graph-theoretical interpretation of the second derivative of clique polynomials

  • We quickely review the basics of clique polynomials

Read more

Summary

Introduction

Polynomials with only real roots are appeared in many branches of theoretical and applied mathematical sciences. They showed that the class of triangle-free graphs has only clique roots This immediately implies another algebraic proof of Mantel’s theorem [1]. In [8], the author obtained a generalization of clique-rootedness of the class of triangle-free graphs He showed that an intersting subclass of chordal graphs has only clique roots. Our main motivation for introducing a new class of graphs with only clique roots is to move forward in the direction of finding a new algebraic proof of Turán’s graph theorem It seems that this idea can be more generalized to prove Turán-type extremal results. We state and prove the main result of our paper which asserts that the class of 2-connected K5-free chordal graphs has only clique roots. We conclude the paper with several interesting open questions and conjectures

Basic definitions and notations
Clique polynomials
Chordal graphs
Main results
Open questions and conjectures
Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

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.