Zagreb indices of subgroup generating bipartite graph

TL;DR

This paper derives formulas for Zagreb indices of a subgroup generating bipartite graph of a group, explores conditions for the Hansen-Vuki{}evi{\u0107} conjecture, and computes various topological indices for specific groups.

Contribution

It introduces explicit expressions for Zagreb indices of the subgroup generating bipartite graph and verifies the Hansen-Vuki{}evi{\u0107} conjecture for certain classes of groups.

Findings

Zagreb indices formulas for $B(G)$ are derived.

Conditions under which $B(G)$ satisfies Hansen-Vuki{}evi{\u0107} conjecture are identified.

Computed various topological indices for specific groups.

Abstract

Let $G$ be a group and $L(G)$ be the set of all subgroups of $G$. The subgroup generating bipartite graph $\mathcal{B}(G)$ defined on $G$ is a bipartite graph whose vertex set is partitioned into two sets $G \times G$ and $L(G)$, and two vertices $(a, b) \in G \times G$ and $H \in L(G)$ are adjacent if $H$ is generated by $a$ and $b$. In this paper, we deduce expressions for first and second Zagreb indices of $\mathcal{B}(G)$ and obtain a condition such that $\mathcal{B}(G)$ satisfy Hansen-Vuki{\v{c}}evi{\'c} conjecture [Hansen, P. and Vuki{\v{c}}evi{\'c}, D. Comparing the Zagreb indices, {\em Croatica Chemica Acta}, \textbf{80}(2), 165-168, 2007]. It is shown that $\mathcal{B}(G)$ satisfies Hansen-Vuki{\v{c}}evi{\'c} conjecture if $G$ is a cyclic group of order $2p, 2p^2, 4p$, $4p^2$ and $p^n$; dihedral group of order $2p$ and $2p^2$; and dicyclic group of order $4p$ and $4p^2$ for any prime $p$. While computing Zagreb indices of $\mathcal{B}(G)$ we have computed $\deg_{\mathcal{B}(G)}(H)$ for all $H \in L(G)$ for the above mentioned groups. Using these information we also compute Randic Connectivity index, Atom-Bond Connectivity index, Geometric-Arithmetic index, Harmonic index and Sum-Connectivity index of $\mathcal{B}(G)$.