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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