Results 21 to 30 of about 1,202 (110)
Stability for the Erdős-Rothschild problem
Forum of Mathematics, Sigma, 2023 Given a sequence $\boldsymbol {k} := (k_1,\ldots ,k_s)$ of natural numbers and 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 some interconnections between combinatorial optimization and extremal graph theory [PDF]
, 2004 The uniting feature of combinatorial optimization and extremal graph theory is that in both areas one should find extrema of a function defined in most cases on a finite set.
Cvetković Dragoš M. +2 more
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A STUDY OF INERTIA INDICES, SIGNATURE AND NULLITY OF V-PHENYLENIC $[m,n]$
, 2020 A molecular/chemical graph is hydrogen depleted chemical structure in which vertices denote atoms and edges denote the bonds. Topological descriptors are the numerical indices based on the topology of the atoms and their bonds (chemical conformation ...
Zheng-Qing Chu +3 more
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Rainbow spanning structures in graph and hypergraph systems
Forum of Mathematics, Sigma, 2023 We study the following rainbow version of subgraph containment problems in a family of (hyper)graphs, which generalizes the classical subgraph containment problems in a single host graph. For a collection $\mathit {\mathbf {G}}=\{G_1, G_2,\ldots , G_{
Yangyang Cheng +3 more
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Extremal problems of double stars [PDF]
Discrete Mathematics & Theoretical Computer Science, 2023 In a generalized Tur\'an problem, two graphs $H$ and $F$ are given and the question is the maximum number of copies of $H$ in an $F$-free graph of order $n$. In this paper, we study the number of double stars $S_{k,l}$ in triangle-free graphs.
Ervin Győri +2 more
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Large butterfly Cayley graphs and digraphs [PDF]
, 2017 We present families of large undirected and directed Cayley graphs whose construction is related to butterfly networks. One approach yields, for every large $k$ and for values of $d$ taken from a large interval, the largest known Cayley graphs and ...
Bevan, David
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The Hilton-Spencer Cycle Theorems Via Katona’s Shadow Intersection Theorem
Discussiones Mathematicae Graph Theory, 2023 A family 𝒜 of sets is said to be intersecting if every two sets in 𝒜 intersect. An intersecting family is said to be trivial if its sets have a common element.
Borg Peter, Feghali Carl
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More on Comparison Between First Geometric-Arithmetic Index and Atom-Bond Connectivity Index [PDF]
, 2015 The first geometric-arithmetic (GA) index and atom-bond connectivity (ABC) index are molecular structure descriptors which play a significant role in quantitative structure-property relationship (QSPR) and quantitative structure-activity relationship ...
Akbar Ali +3 more
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Some inequalities for the multiplicative sum Zagreb index of graph operations
, 2015 The multiplicative sum Zagreb index is defined for a simple graph G as the product of the terms dG(u)+dG(v) over all edges uv∈E(G) , where dG(u) denotes the degree of the vertex u of G .
M. Azari, A. Iranmanesh
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EXTREMAL UNICYCLIC GRAPHS WITH RESPECT TO ADDITIVELY WEIGHTED HARARY INDEX [PDF]
, 2013 In this paper we define cycle-star graphCSk;n k to be a graph onn vertices consisting of the cycle of lengthk andn k leafs appended to the same vertex of the cycle.
J. Sedlar
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