AIMS Mathematics 2024, 9(6): 15988-15995
Published: 07 May 2024
An edge-coloring of a graph is an assignment of colors to its edges so that no two edges incident to the same vertex receive the same color. The chromatic index of , denoted by , is the least for which has a edge-coloring. Graphs with are said to be Class 1, and graphs with are said to be Class 2. Let be a graph with , , and be a sequence of vertex-disjoint graphs with , . The generalized lexicographic product of and is a simple graph with vertex set , in which is adjacent to if and only if either and or . If is a complete graph with order 2, then denotes a join of vertex-disjoint graphs and . If for , then , where denotes the lexicographic product of two graphs and . In this paper, we provide sufficient conditions for the generalized lexicographic product of and to be Class 1, where all graphs in have the same number of vertices.