A Survey on the Randić Index
نویسندگان
چکیده
The general Randić index Rα(G) of a (chemical) graph G, is defined as the sum of the weights (d(u)d(v))α of all edges uv of G, where d(u) denotes the degree of a vertex u in G and α an arbitrary real number, which is called the Randić index or connectivity index (or branching index) for α = −1/2 proposed by Milan Randić in 1975. The paper outlines the results known for the (general) Randić index of (chemical) graphs. Some very new results are released. We classify the results into the following categories: extremal values and extremal graphs of Randić index, general Randić index, zeroth-order general Randić index, higher-order Randić index. A few conjectures and open problems are mentioned.
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