Results 21 to 30 of about 5,888,750 (277)
On a valence problem in extremal graph theory
Discrete Mathematics, 1973 Vorliegende Arbeit bezieht sich auf nicht-orientierte, Schlingen und mehrfache Kanten nicht enhaltende Graphen. Bezeichne \(L\) einen solchen vom vollständigen \(p\)-Graphen \(K_p\) verschiedenen \(p\)-chromatischen Graphen, welcher eine Kante \(e\) so enthält, daß \(L-e\) ein \((p-1)\)-chromatischer Graph ist. Als Hauptergebnis der vorliegenden Arbeit
M Simonovits
exaly +4 more sources
Proofs by Transformation in Extremal Graph Theory. [PDF]
, 2022 A graph is a mathematical model representing binary relationships between elements of a set. It is composed of two sets: the set of the elements called the vertices and a set of pairs of vertices called the edges. Graphs appear in many fields from computer networks to chemistry and even scheduling.
Devillez, Gauvain
core +4 more sources
It Is Better to Be Semi-Regular When You Have a Low Degree. [PDF]
Entropy (Basel)We study the algebraic connectivity for several classes of random semi-regular graphs. For large random semi-regular bipartite graphs, we explicitly compute both their algebraic connectivity as well as the full spectrum distribution. For an integer d∈3,7,
Kolokolnikov T.
europepmc +2 more sources
On tricyclic graphs with maximum atom-bond sum-connectivity index. [PDF]
HeliyonThe sum-connectivity, Randić, and atom-bond connectivity indices have a prominent place among those topological indices that depend on the graph's vertex degrees.
Noureen S +5 more
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Exponential second Zagreb index of chemical trees [PDF]
Transactions on Combinatorics, 2021 Cruz, Monsalve and Rada [Extremal values of vertex-degree-based topological indices of chemical trees, Appl. Math. Comput. 380 (2020) 125281] posed an open problem to find the maximum value of the exponential second Zagreb index for chemical ...
Selvaraj Balachandran, Tomas Vetrik
doaj +1 more source
Note on the temperature Sombor index
Vojnotehnički Glasnik, 2023 Introduction/purpose: The temperature of a vertex of a graph of the order n is defined as d/(n-d), where d is the vertex degree. The temperature variant of the Sombor index is investigated and several of its properties established. Methods: Combinatorial
Ivan Gutman
doaj +1 more source
Guessing Numbers and Extremal Graph Theory
The Electronic Journal of Combinatorics, 2022 For a given number of colors, $s$, the guessing number of a graph is the (base $s$) logarithm of the cardinality of the largest family of colorings of the vertex set of the graph such that the color of each vertex can be determined from the colors of the vertices in its neighborhood.
Jo Martin, Puck Rombach
openaire +4 more sources
Reducing the maximum degree of a graph: comparisons of bounds
Theory and Applications of Graphs, 2021 Let $\lambda(G)$ be the smallest number of vertices that can be removed from a non-empty graph $G$ so that the resulting graph has a smaller maximum degree.
Peter Borg
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On the Boundary of Incidence Energy and Its Extremum Structure of Tricycle Graphs
Frontiers in Physics, 2020 With the wide application of graph theory in circuit layout, signal flow chart and power system, more and more attention has been paid to the network topology analysis method of graph theory.
Hongyan Lu, Zhongxun Zhu
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A note on the Ramsey numbers for theta graphs versus the wheel of order 5
AKCE International Journal of Graphs and Combinatorics, 2018 The study of exact values and bounds on the Ramsey numbers of graphs forms an important family of problems in the extremal graph theory. For a set of graphs S and a graph F , the Ramsey number R (S , F) is the smallest positive integer r such that for ...
Mohammed M.M. Jaradat +3 more
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