Volume 56 | Number 5 | Year 2018 | Article Id. IJMTT-V56P544 | DOI : https://doi.org/10.14445/22315373/IJMTT-V56P544

The degree of a vertex of a molecular graph is the number of first neighbors of the vertex. Sum degree and Multiplication degree of the vertex of a molecular graph is the sum of the degree of the vertices of the neighborhood vertices of the vertex and product of the degree of the vertices of the neighborhood vertices of a vertex respectively. The R degree of the vertex of a molecular graph is the sum of the sum degree of the vertex and the Multiplication degree of the vertex. The concept of degree in graph theory is closely interconnected to the concept of valence in chemistry. In this paper, some formulas are obtained for calculating the vertex based topological R index of the some Bridge graphs.

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Dr. A. Sumathi, "R Index of Some Bridge Graphs," *International Journal of Mathematics Trends and Technology (IJMTT)*, vol. 56, no. 5, pp. 331-334, 2018. *Crossref*, https://doi.org/10.14445/22315373/IJMTT-V56P544