Graphs with Smallest Forgotten Index

Document Type : Research Paper

Authors

1 University of Kragujevac, Serbia

2 University of Kashan

Abstract

The forgotten topological index of a molecular graph G is defined as F(G)=\sum_{v\in V(G)}d^{3}(v), where d(u) denotes the degree of vertex u in G. The first through the sixth smallest forgotten indices among all trees, the first through the third smallest forgotten indices among all connected graph with cyclomatic number \gamma=1,2, the first through the fourth for \gamma=3, and the first and the second for \gamma=4,5 are determined. These results are compared with those obtained for the first Zagreb index.

Keywords

Main Subjects


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