Results 21 to 30 of about 41,896 (267)
On Certain Types of Neutrosophic Fuzzy Graphs
Pan-American Journal of Mathematics, 2022 In this paper, we introduce some types of NF graphs and operations. Also we define the partial NF subgraph, spanning NF subgraph, strong degree of the vertex, total strong degree of the vertex and its properties are included.
Alias B. Khalaf, Prithivirajan Padma
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A Golden Ratio Inequality for Vertex Degrees of Graphs [PDF]
The American Mathematical Monthly, 2019 Motivated by the study of the crossing number of graphs, it is shown that, for trees, the sum of the products of the degrees of the end-vertices of all edges has an upper bound in terms of the sum of all vertex degrees to the power of $ ^2$, where $ $ is the golden ratio. The exponent $ ^2$ is best possible.
Fiachra Knox, Bojan Mohar, David R. Wood
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Sufficient Conditions for Graphs to Be k-Connected, Maximally Connected, and Super-Connected
Complexity, 2021 Let G be a connected graph with minimum degree δG and vertex-connectivity κG. The graph G is k-connected if κG≥k, maximally connected if κG=δG, and super-connected if every minimum vertex-cut isolates a vertex of minimum degree. In this paper, we present
Zhen-Mu Hong +3 more
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Limit laws of planar maps with prescribed vertex degrees [PDF]
Combinatorics, Probability and Computing, 2019 AbstractWe prove a generalmulti-dimensional central limit theorem for the expected number of vertices of a given degree in the family of planar maps whose vertex degrees are restricted to an arbitrary (finite or infinite) set of positive integersD. Our results rely on a classical bijection with mobiles (objects exhibiting a tree structure), combined ...
Collet, G., Drmota, M., Klausner, L. D.
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Minimum generalized degree distance of n-vertex tricyclic graphs [PDF]
Journal of Inequalities and Applications, 2013 Abstract In (Hamzeh et al. in Stud. Univ. Babeş-Bolyai, Chem., 4:73-85, 2012), we introduced a generalization of a degree distance of graphs as a new topological index. In this paper, we characterize the n-vertex tricyclic graphs which have the minimum generalized degree distance. MSC:05C12, 05C35, 05C05.
Hamzeh, Asma +2 more
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Vertex degrees of planar graphs
Journal of Combinatorial Theory, Series B, 1979 AbstractLet G be a planar graph having n vertices with vertex degrees d1, d2,…,dn. It is shown that Σi=1ndi2 ≤ 2n2 + O(n). The main term in this upper bound is best possible.
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Bounding the feedback vertex number of digraphs in terms of vertex degrees
Discrete Applied Mathematics, 2011 The Turan bound is a famous result in graph theory, which relates the independence number of an undirected graph to its edge density. Also the Caro-Wei inequality, which gives a more refined bound in terms of the vertex degree sequence of a graph, might be regarded today as a classical result. We show how these statements can be generalized to directed
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Random Graphs' Robustness in Random Environment
Austrian Journal of Statistics, 2017 We consider configuration graphs the vertex degrees of which are independent and follow the power-law distribution. Random graphs dynamics takes place in a random environment with the parameter of vertex degree distribution following uniform ...
Marina Leri, Yury Pavlov
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Conjecture Involving Arithmetic-Geometric and Geometric-Arithmetic Indices
Discrete Dynamics in Nature and Society, 2022 The geometric-arithmetic (GA) index of a graph G is the sum of the ratios of geometric and arithmetic means of end-vertex degrees of edges of G. Similarly, the arithmetic-geometric (AG) index of G is defined. Recently, Vujošević et al. conjectured that a
Zainab Alsheekhhussain +3 more
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Structural biology of ferritin nanocages
FEBS Letters, EarlyView.Ferritin is a conserved iron‐storage protein that sequesters iron as a ferric mineral core within a nanocage, protecting cells from oxidative damage and maintaining iron homeostasis. This review discusses ferritin biology, structure, and function, and highlights recent cryo‐EM studies revealing mechanisms of ferritinophagy, cellular iron uptake, and ...
Eloise Mastrangelo, Flavio Di Pisa
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