In this study, we investigate a new kind of mean labeling of graph. The ladder graph plays an important role in the area of communication networks, coding theory, and transportation engineering. Also, we found interesting new results corresponding to classical mean labeling for some ladder-related graphs and corona of ladder graphs with suitable examples.
1. Introduction and Preliminaries
All through this paper, by a graph, we mean an undirected, simple, and finite graph. For documentations and phrasing, we follow [1–6]. For a point-by-point review on graph labeling, refer [7].
Let be a path on nodes denoted by , where , and with lines denoted by , where , where is the line joining the vertices and . On each edge , erect a ladder with steps including the edge , for . The resulting graph is called the one-sided step graph, and it is denoted by . Let be a path on vertices , where and with edges , where is the line joining the vertices and . On each edge , we erect a ladder with ‘’ steps including the edge , for , and on each , we erect a ladder with steps including , for . The graph thus obtained is called the double-sided step graph, and it is denoted by . Let and be any two graphs with and vertices, respectively. Then, is the cartesian product of two graphs. A ladder graph is the graph . The graph is obtained from by attaching pendant vertices to each vertex of . The triangular ladder , for , is a graph obtained from two paths by and by adding the edges and . The slanting ladder is a graph obtained from two paths and by joining each , with . The graph having the vertices , and its edge set is .
2. Literature Survey
The origin of graph labeling called graceful labeling was characterized by Rosa in [8] and the mean labeling of graphs was introduced by Somasundram et al. in [9]. In [10], Arockiaraj et al. presented the idea of -root square mean labeling of the graphs and examined its meanness [11]. Durai Baskar and Arockiaraj talked about the -geometric meanness of some ladders in [12]. Dafik et al. researched the antimagicness of the graphs including the graph in [13]. Durai Baskar considered the logarithmic meanness in [14] and Rajesh Kannan et al. characterized idea of exponential mean graphs in [15]. In addition, more concepts of ladder graphs and related concepts have been studied in [16–24]. Recently, Muhiuddin et al. have applied various related concepts on graphs in different aspects (see, e.g., [25–31]).
3. Methodology
A labeling on a graph with vertices and edges is called a Smarandache mean labeling, for an integer and , if is injective and the induced function defined byfor all , is bijective.
Particularly, if and , such a Smarandache mean labeling is the classical mean labeling on the graph. A function is known as a classical mean labeling of a graph with nodes and edges if is injective and the incited edge assignment function characterized asfor all , is bijective. A graph that concedes a classical mean labeling is said to be classical mean graph.
A classical mean labeling of is shown in Figure 1.