Chromatic Number of the Corona Product of Complete Graph and Star Graph

Authors

  • Mustika Asmarani Universitas Pendidikan Indonesia
  • Kartika Yulianti Universitas Pendidikan Indonesia
  • Endang Cahya Mulyaning Asih Universitas Pendidikan Indonesia

DOI:

https://doi.org/10.24252/msa.v13i2.56235

Keywords:

Coloring vertex, Chromatic number, Corona product, Complete graph, Star graph

Abstract

In this paper, we determine the chromatic number of the corona product of complete graph $K_n$ and star graph $K_{1,m}$. Determination of the chromatic numbers is done by observing patterns, constructing conjectures, and proving them formally. We found that the chromatic number of the corona product of complete graph $K_n$ and star graph $K_{1,m}$ is $\chi\left(K_n\odot K_{1,m}\right)=\left\{\begin{matrix}3,\ \ n=1,2\\n,\ n=3,4,\ldots,\ k\\\end{matrix}\right.$, and the chromatic number of the corona product of star graph $K_{1,m}$ and complete graph $K_n$ is $\chi\left(K_{1,m}\odot K_n\right)=n+1,\ n=1,2,\ldots,\ k$. Furthermore, using Matlab software, a program is created to visualize the coloring of the vertices based on the formula that has been obtained.

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Published

2025-11-21

How to Cite

[1]
M. Asmarani, K. Yulianti, and E. C. Mulyaning Asih, “Chromatic Number of the Corona Product of Complete Graph and Star Graph”, MSA, vol. 13, no. 2, pp. 116–122, Nov. 2025.