Results 11 to 20 of about 314 (174)

The Second Maximum Mostar Index of Unicyclic Graphs With Given Diameter

Journal of Mathematics
Topological invariants are key tools for studying the physicochemical and thermodynamic properties of chemical compounds. Recently, a new bond-additive distance-based graph invariant called the Mostar index has been developed.
Muhammad Amer Qureshi, Asad Ullah, Parvez Ali, Emad E. Mahmoud, Melaku Berhe Belay   +4 more
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The Extremal Unicyclic Graphs With Given Girth for Exponential VDB Topological Indices

Journal of Mathematics
Topological indices are widely used molecular structure descriptors in chemistry and pharmaceutics, which help analyze and predict the physicochemical properties and biological activity of compounds.
Zhenhua Su, Zikai Tang
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Extremal Values on the General Degree–Eccentricity Index of Unicyclic Graphs of Fixed Diameter

Journal of Mathematics
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 VG represent the vertex set of graph G, dGv denotes the degree of vertex v, and ecGv is the eccentricity of v in G ...
Mesfin Masre
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Contraharmonic Index: Extremal Results for Unicyclic Graphs and Bounds for General Graphs

Journal of Mathematics
Let G be a graph with edge set EG. The degree of a vertex w in G is denoted by dw. The contraharmonic index of G is defined as CHG=∑uv∈EGdu+dv−1du2+dv2.
Abdulaziz Mutlaq Alotaibi, Akbar Ali
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The inverse of the incidence matrix of a unicyclic graph [PDF]

Linear and Multilinear Algebra, 2022
The vertex-edge incidence matrix of a (connected) unicyclic graph G is a square matrix which is invertible if and only if the cycle of G is an odd cycle. A combinatorial formula of the inverse of the incidence matrix of an odd unicyclic graph was known.
Hessert, Ryan, Mallik, Sudipta
openaire   +2 more sources

Unicyclic Graphs with the Fourth Extremal Wiener Indices

Journal of Chemistry, 2020
A graph is called unicyclic if the graph contains exactly one cycle. Unicyclic graphs with the fourth extremal Wiener indices are characterized. It is shown that, among all unicyclic graphs with n≥8 vertices, C5Sn−4 and C2u1,u2S3,Sn−4 attain the fourth ...
Guangfu Wang, Yujun Yang, Yuliang Cao, Shoujun Xu   +3 more
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On Variable Sum Exdeg Indices of Quasi-Tree Graphs and Unicyclic Graphs

Discrete Dynamics in Nature and Society, 2020
In this work, by using the properties of the variable sum exdeg indices and analyzing the structure of the quasi-tree graphs and unicyclic graphs, the minimum and maximum variable sum exdeg indices of quasi-tree graphs and quasi-tree graphs with perfect ...
Xiaoling Sun, Jianwei Du
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Characterization of Extremal Unicyclic Graphs Using F-Coindex

Complexity, 2021
The study of forgotten index and coindex for the molecular structures of some special chemical graphs (compounds and drugs) has proven significant in medical and pharmaceutical drug design fields by making reliable statistical conclusion about biological
Muhammad Imran, Yasir Ali, Zainab Bibi, Muhammad Saad Ghafar   +3 more
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On the core of a unicyclic graph

Ars Mathematica Contemporanea, 2012
8 pages, 5 ...
Vadim E. Levit, Eugen Mandrescu
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Generating graceful unicyclic graphs from a given forest

AKCE International Journal of Graphs and Combinatorics, 2020
Acharya (1982) proved that every connected graph can be embedded in a graceful graph. The generalization of this result that, any set of graphs can be packed into a graceful graph was proved by Sethuraman and Elumalai (2005). Recently, Sethuraman et al. (
G. Sethuraman, V. Murugan
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