Research Article

INJECTIVE COLORING OF CENTRAL GRAPHS

Volume: 16 Number: 3 March 17, 2026

INJECTIVE COLORING OF CENTRAL GRAPHS

Abstract

For a given graph $G=(V(G),E(G))$, researchers have introduced different colorings based on the distances of the vertices. An injective coloring of a graph $G$ is an assignment of colors to the vertices of $G$ such that no two vertices with a common neighbor receive the same color. The injective chromatic number of $G$, denoted by $\chi_{i}(G)$, is the minimum number of colors required for an injective coloring of $G$. The concept of a central graph of any graph has been a widely studied topic among mathematical researchers and graph theorists nowadays. The central graph of a given graph $G$, denoted by $C(G)$, is the graph obtained by subdividing each edge of $G$ exactly once and also adding an edge between each pair of non-adjacent vertices of $G$. In this work, we present some results on injective coloring of central graph $C(G)$ of $G$. We show that for a graph $G$ of order $n$ and maximum degree $\Delta(G)$, $$n-1\le \chi_{i}(C(G))\leq n^{2}-3n-(n-3)\Delta(G)+3.$$ Next, we will closely examine the injective chromatic number of the central graph of some special graphs and trees. Finally, for any graph $H$, and the corona product ($H\circ K_1$), ($H\circ K_2$), we will have a precise determination of the injective chromatic number of $C(H\circ K_1)$ and $C(H\circ K_2)$ in terms of $\chi_{i}(C(H))$ and order of $H$.

Keywords

References

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Details

Primary Language

English

Subjects

Combinatorics and Discrete Mathematics (Excl. Physical Combinatorics)

Journal Section

Research Article

Publication Date

March 17, 2026

Submission Date

January 31, 2025

Acceptance Date

May 26, 2025

Published in Issue

Year 2026 Volume: 16 Number: 3

APA
Mirdamad, S. S., & Mojdeh, D. A. (2026). INJECTIVE COLORING OF CENTRAL GRAPHS. TWMS Journal of Applied and Engineering Mathematics, 16(3), 369-385. https://izlik.org/JA66WS57EU
AMA
1.Mirdamad SS, Mojdeh DA. INJECTIVE COLORING OF CENTRAL GRAPHS. JAEM. 2026;16(3):369-385. https://izlik.org/JA66WS57EU
Chicago
Mirdamad, Shahrzad Sadat, and Doost Ali Mojdeh. 2026. “INJECTIVE COLORING OF CENTRAL GRAPHS”. TWMS Journal of Applied and Engineering Mathematics 16 (3): 369-85. https://izlik.org/JA66WS57EU.
EndNote
Mirdamad SS, Mojdeh DA (March 1, 2026) INJECTIVE COLORING OF CENTRAL GRAPHS. TWMS Journal of Applied and Engineering Mathematics 16 3 369–385.
IEEE
[1]S. S. Mirdamad and D. A. Mojdeh, “INJECTIVE COLORING OF CENTRAL GRAPHS”, JAEM, vol. 16, no. 3, pp. 369–385, Mar. 2026, [Online]. Available: https://izlik.org/JA66WS57EU
ISNAD
Mirdamad, Shahrzad Sadat - Mojdeh, Doost Ali. “INJECTIVE COLORING OF CENTRAL GRAPHS”. TWMS Journal of Applied and Engineering Mathematics 16/3 (March 1, 2026): 369-385. https://izlik.org/JA66WS57EU.
JAMA
1.Mirdamad SS, Mojdeh DA. INJECTIVE COLORING OF CENTRAL GRAPHS. JAEM. 2026;16:369–385.
MLA
Mirdamad, Shahrzad Sadat, and Doost Ali Mojdeh. “INJECTIVE COLORING OF CENTRAL GRAPHS”. TWMS Journal of Applied and Engineering Mathematics, vol. 16, no. 3, Mar. 2026, pp. 369-85, https://izlik.org/JA66WS57EU.
Vancouver
1.Shahrzad Sadat Mirdamad, Doost Ali Mojdeh. INJECTIVE COLORING OF CENTRAL GRAPHS. JAEM [Internet]. 2026 Mar. 1;16(3):369-85. Available from: https://izlik.org/JA66WS57EU