In-domination and out-domination numbers of unidirectional graphs
Sanal Kumardrssanalkumar@gmail.comDepartment of Sciences and MathematicsFaculty of MathematicsUniversity of Technology and Applied SciencesSultanate of OmanView full profile →
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- Received:
- 01 Jun 2023
- Published Online:
- 17 Jul 2026
- Article type:
- Research Article
- Language:
- EN
- Article no.:
- JDMSC-2701
- Pages:
- 2897–2904
Abstract
The diverging unidirectional star graph is the unidirectional star graph with n+1 nodes(vertices) and n arcs, n nodes of in-degree 1 and out-degree 0. The converging unidirectional graph consisting of n+1 vertices and n arcs, where n vertices have out-degree one and in-degree zero, with all arcs oriented towards the single central vertex. A diverging unidirectional perfect binary tree is a directed tree where each internal vertex, except for the root, has an out-degree of two and in-degree of one, with all leaves at the same depth; conversely, a converging unidirectional perfect tree has the opposite structure. Here, we investigate the in-domination and out-domination numbers associated with these classes of directed graph. Explicit expressions for the same numbers are derived for the afore mentioned families of graphs as well as for unidirectional non-homogeneous super caterpillar graphs.
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References
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