Star-critical connected Ramsey numbers for 2-colorings of complete graphs

Document Type : Research Paper

Authors

1 Department of Mathematics, Central University of Haryana, Haryana, India

2 Department of Mathematics, Central University of Haryana, Haryana, India.

3 Department of Mathematics and Computer Science, Western Carolina University, Cullowhee, NC 28723

Abstract

This paper builds upon Sumner's work by further investigating the concept of connected Ramsey numbers, specifically focusing on star-critical connected Ramsey numbers. We obtain star-critical connected Ramsey numbers for several cases of trees versus complete graphs, stars versus stars, and paths versus paths. The connected Ramsey number for a star versus $K_3$ is also evaluated. Exact values are also obtained for the connected Ramsey numbers of $K_{1,n}$ versus $K_3$. This research explores the interplay between connectivity and graph coloring within the context of Ramsey theory.

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Main Subjects


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Volume 14, Issue 4 - Serial Number 4
December 2025
Pages 211-222
  • Receive Date: 28 February 2024
  • Revise Date: 01 August 2024
  • Accept Date: 13 August 2024
  • Published Online: 01 December 2025