Results 31 to 40 of about 55 (55)
Location of zeros for the partition function of the Ising model on bounded degree graphs
Abstract The seminal Lee–Yang theorem states that for any graph the zeros of the partition function of the ferromagnetic Ising model lie on the unit circle in C. In fact, the union of the zeros of all graphs is dense on the unit circle. In this paper, we study the location of the zeros for the class of graphs of bounded maximum degree d⩾3, both in the ...
Han Peters, Guus Regts
wiley +1 more source
Similarly to Wiener index, hyper-Wiener index of a connected graph is a widely applied topological index measuring the compactness of the structure described by the given graph. Hyper-Wiener index is the sum of the distances plus the squares of distances
Mujahed Hamzeh, Nagy Benedek
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Topological Indices of Para-line Graphs of V-Phenylenic Nanostructures
The degree-based topological indices are numerical graph invariants which are used to correlate the physical and chemical properties of a molecule with its structure.
Nadeem Imran +3 more
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Sharp Upper Bounds on the Clar Number of Fullerene Graphs
The Clar number of a fullerene graph with n vertices is bounded above by ⌊n/6⌋ − 2 and this bound has been improved to ⌊n/6⌋ − 3 when n is congruent to 2 modulo 6.
Gao Yang, Zhang Heping
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For 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
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In graph theory, the Randic index (R) is a topological graph invariant widely used as a physicochemical descriptor in the mathematical modeling of molecular structures. However, traditional molecular graphs fail to capture the heterogeneity of chemical bonds, since they treat all edges as uniform, ignoring variations in bond lengths and strengths.
Ying Wang +5 more
wiley +1 more source
The Sanskruti index of trees and unicyclic graphs
The Sanskruti index of a graph G is defined as S(G)=∑uv∈E(G)sG(u)sG(v)sG(u)+sG(v)−23,$$\begin{align*}S(G)=\sum_{uv\in{}E(G)}{\left(\frac{s_G(u)s_G(v)}{s_G(u)+s_G(v)-2}\right)}^3, \end{align*}$$where sG(u) is the sum of the degrees of the neighbors of a ...
Deng Fei +6 more
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Extremal Values on the General Degree–Eccentricity Index of Unicyclic Graphs of Fixed Diameter
For a connected graph G and two real numbers a, b, the general degree–eccentricity index of G is given by DEIa,bG=∑v∈VGdGavecGbv, where V(G) represent the vertex set of graph G, dG(v) denotes the degree of vertex v, and ecG(v) is the eccentricity of v in G, that is, the maximum distance from v to another vertex of G. This index generalizes several well‐
Mesfin Masre, G. Muhiuddin
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Computing Some Topological Indices of Two Kinds of Dendrimer Graphs G[n] and H[n]
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
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Upper bounds for the global cyclicity index
We find new upper bounds for the global cyclicity index, a variant of the Kirchhoff index, and discuss the wide family of graphs for which the bounds are attained.
Palacios José Luis
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