Results 31 to 40 of about 238 (93)
A note on the problem of finding a (3, 9)‐cage
International Journal of Mathematics and Mathematical Sciences, Volume 8, Issue 4, Page 817-820, 1985., 1985 In this paper, we discuss The poblem of finding a (3, 9)‐cage. A hamiltonian graph with girth 9 and 54 vertices is given. Except four vertices, each of the remaining vertices of this graph has valency Three. This graph is obtained with the aid of a computer.
P. K. Wong
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International Journal of Mathematics and Mathematical Sciences, Volume 5, Issue 3, Page 553-564, 1982., 1982 A graph is subeulerian if it is spanned by an eulerian supergraph. Boesch, Suffel and Tindell have characterized the class of subeulerian graphs and determined the minimum number of additional lines required to make a subeulerian graph eulerian. In this paper, we consider the related notion of a subsemi‐eulerian graph, i.e.
Charles Suffel +3 more
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ON TOPOLOGICAL PROPERTIES OF PLANE GRAPHS BY USING LINE OPERATOR ON THEIR SUBDIVISIONS
International Journal of Apllied Mathematics, 2018 In this paper, we will compute some topological indices such as Zagreb indices M1(G), M2(G), M3(G), Zagreb coindices M1(G), M1(G), M2(G), M2(G)), M2(G), hyper-Zagreb index HM(G), atom-bond connectivity index ABC(G), sum connectivity index χ(G ...
Mohamad Nazri Husin +4 more
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On extremal numbers of the triangle plus the four-cycle
Forum of Mathematics, SigmaFor a family $\mathcal {F}$ of graphs, let ${\mathrm {ex}}(n,\mathcal {F})$ denote the maximum number of edges in an n-vertex graph which contains none of the members of $\mathcal {F}$ as a subgraph.
Jie Ma, Tianchi Yang
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Hyper-Wiener indices of polyphenyl chains and polyphenyl spiders
Open Mathematics, 2019 Let G be a connected graph and u and v two vertices of G. The hyper-Wiener index of graph G is WW(G)=12∑u,v∈V(G)(dG(u,v)+dG2(u,v))$\begin{array}{} WW(G)=\frac{1}{2}\sum\limits_{u,v\in V(G)}(d_{G}(u,v)+d^{2}_{G}(u,v)) \end{array}$, where dG(u, v) is the ...
Wu Tingzeng, Lü Huazhong
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Exact solutions to the Erdős-Rothschild problem
Forum of Mathematics, SigmaLet $\boldsymbol {k} := (k_1,\ldots ,k_s)$ be a sequence of natural numbers. For a graph G, let $F(G;\boldsymbol {k})$ denote the number of colourings of the edges of G with colours $1,\dots ,s$ such that, for every $c \in \{1 ...
Oleg Pikhurko, Katherine Staden
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On the Metric Dimension of Directed and Undirected Circulant Graphs
Discussiones Mathematicae Graph Theory, 2020 The undirected circulant graph Cn(±1, ±2, . . . , ±t) consists of vertices v0, v1, . . . , vn−1 and undirected edges vivi+j, where 0 ≤ i ≤ n − 1, 1 ≤ j ≤ t (2 ≤ t ≤ n2{n \over 2} ), and the directed circulant graph Cn(1, t) consists of vertices v0, v1, .
Vetrík Tomáš
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Spectra of Orders for k-Regular Graphs of Girth g
Discussiones Mathematicae Graph Theory, 2021 A (k, g)-graph is a k-regular graph of girth g. Given k ≥ 2 and g ≥ 3, infinitely many (k, g)-graphs of infinitely many orders are known to exist. Our goal, for given k and g, is the classification of all orders n for which a (k, g)-graph of order n ...
Jajcay Robert, Raiman Tom
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Extermal properties of Zagreb coindices and degree distance of graphs
, 2010 The degree distance, Zagreb coindices and reverse degree distance of a connected graph have been studied in mathematical chemistry. In this paper some new extremal values of these topological invariants over some special classes of graphs are determined.
S. Hossein-Zadeh, A. Hamzeh, A. Ashrafi
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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
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