Results 31 to 40 of about 124 (74)
Journal of Mathematics, Volume 2025, Issue 1, 2025.The multiplicative sum Zagreb index of a graph G is defined as the product of the sum of the degrees of adjacent vertices of G. A molecular tree is an acyclic connected graph with maximum degree at most 4. A vertex in a molecular tree with degree 3 or 4 is referred to as a branching vertex. In this paper, we consider the class of all molecular trees of
Sadia Noureen +6 more
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Estrada index of hypergraphs via eigenvalues of tensors
, 2021 A uniform hypergraph $\mathcal{H}$ is corresponding to an adjacency tensor $\mathcal{A}_\mathcal{H}$. We define an Estrada index of $\mathcal{H}$ by using all the eigenvalues $\lambda_1,\dots,\lambda_k$ of $\mathcal{A}_\mathcal{H}$ as $\sum_{i=1}^k e ...
Bu, Changjiang, Sun, Lizhu, Zhou, Hong
core
Journal of Mathematics, Volume 2025, Issue 1, 2025.In its crystalline state, the α‐icosahedral nanosheet of boron demonstrates superconductivity and thermal electronic properties. Mathematical research on a graph’s structure yields a graph descriptor, a numerical measure. Chemical graph theory employs connectivity descriptors to analyze molecular structures, providing crucial insights into many ...
Khalil Hadi Hakami +3 more
wiley +1 more source
Some new bounds on resolvent energy of a graph
Open MathematicsLet GG be a simple graph of order nn with eigenvalues λ1≥λ2≥…≥λn.{\lambda }_{1}\ge {\lambda }_{2}\ge \ldots \ge {\lambda }_{n}. The resolvent energy of GG is a spectrum-based graph invariant defined as ER(G)=∑i=1n(n−λi)−1.{\rm{ER}}(G)={\sum }_{i=1}^{n ...
Altındağ İlkay +1 more
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Computing Some Topological Indices of Two Kinds of Dendrimer Graphs G[n] and H[n]
Journal of Mathematics, Volume 2024, Issue 1, 2024.Dendrimer molecules are macromolecules which have many applications in nanosciences, drug delivery, biology, and different areas of sciences. Topological indices of chemical graph theory are numerical descriptor of a molecular structure. The dendrimer graph G[n] is obtained by attaching the new paths P9, joined each pendant vertex of G[n − 1] to ...
Hojat Kaviani +2 more
wiley +1 more source
The minimum matching energy of unicyclic graphs with fixed number of vertices of degree two
Open MathematicsThe number of jj-matchings in a graph HH is denote by m(H,j)m\left(H,j). If for two graphs H1{H}_{1} and H2{H}_{2}, m(H1,j)≥m(H2,j)m\left({H}_{1},j)\ge m\left({H}_{2},j) for all jj, then we write H1≽H2{H}_{1}\succcurlyeq {H}_{2}.
Bai Yongqiang, Ma Hongping, Zhang Xia
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Brouwer's conjecture for the sum of the k largest Laplacian eigenvalues of some graphs
Open MathematicsLet GG be a graph with n(G)n\left(G) vertices and e(G)e\left(G) edges, and Sk(G){S}_{k}\left(G) be the sum of the kk largest Laplacian eigenvalues of GG. Brouwer conjectured that Sk(G)≤e(G)+k+12{S}_{k}\left(G)\le e\left(G)+\left(\phantom{\rule[-0.75em]{}{
Wang Ke +3 more
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On the Harary Estrada index of graphs
Special MatricesLet GG be a connected graph with nn vertices v1,…,vn{v}_{1},\ldots ,{v}_{n}. The Harary matrix of GG, denoted by H(G)H\left(G), is an n×nn\times n matrix with a zero main diagonal, where the (i,j)\left(i,j)-entry is 1d(vi,vj)\frac{1}{d\left({v}_{i},{v}_ ...
Oboudi Mohammad Reza
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The sufficient conditions for $k$-leaf-connected graphs in terms of several topological indices
, 2023 Let $G=(V(G), E(G))$ be a graph with vertex set $V(G)$ and edge set $E(G)$. For $k\geq2$ and given any subset $S\subseteq|V(G)|$ with $|S|=k$, if a graph $G$ of order $|V(G)|\geq k+1$ always has a spanning tree $T$ such that $S$ is precisely the set of ...
Hu, Yang, Ma, Tingyan, Wang, Ligong
core
Main Group Metal ChemistryFor a graph Q=(V,E){\mathbb{Q}}=\left({\mathbb{V}},{\mathbb{E}}), the transformation graph are defined as graphs with vertex set being V(Q)∪E(Q){\mathbb{V}}\left({\mathbb{Q}})\cup {\mathbb{E}}\left({\mathbb{Q}}) and edge set is described following ...
Ali Parvez +5 more
doaj +1 more source