Results 11 to 20 of about 1,119 (103)
Banhatti, revan and hyper-indices of silicon carbide Si2C3-III[n,m]
Open Chemistry, 2021 In recent years, several structure-based properties of the molecular graphs are understood through the chemical graph theory. The molecular graph GG of a molecule consists of vertices and edges, where vertices represent the atoms in a molecule and edges ...
Zhao Dongming +6 more
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Discussiones Mathematicae Graph Theory, 2022 The Turán number of a graph H, denoted by ex(n, H), is the maximum number of edges of an n-vertex simple graph having no H as a subgraph. Let Sℓ denote the star on ℓ + 1 vertices, and let k · Sℓ denote k disjoint copies of Sℓ. Erdős and Gallai determined
Li Sha-Sha, Yin Jian-Hua, Li Jia-Yun
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Comparing Eccentricity-Based Graph Invariants
Discussiones Mathematicae Graph Theory, 2020 The first and second Zagreb eccentricity indices (EM1 and EM2), the eccentric distance sum (EDS), and the connective eccentricity index (CEI) are all recently conceived eccentricity-based graph invariants, some of which found applications in chemistry ...
Hua Hongbo, Wang Hongzhuan, Gutman Ivan
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A Note on Packing of Uniform Hypergraphs
Discussiones Mathematicae Graph Theory, 2022 We say that two n-vertex hypergraphs H1 and H2 pack if they can be found as edge-disjoint subhypergraphs of the complete hypergraph Kn. Whilst the problem of packing of graphs (i.e., 2-uniform hypergraphs) has been studied extensively since seventies ...
Konarski Jerzy +2 more
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A proof of the stability of extremal graphs, Simonovits' stability from Szemer\'edi's regularity [PDF]
, 2015 The following sharpening of Tur\'an's theorem is proved. Let $T_{n,p}$ denote the complete $p$--partite graph of order $n$ having the maximum number of edges. If $G$ is an $n$-vertex $K_{p+1}$-free graph with $e(T_{n,p})-t$ edges then there exists an (at
Füredi, Zoltán
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Extremal numbers for odd cycles [PDF]
, 2013 We describe the C_{2k+1}-free graphs on n vertices with maximum number of edges. The extremal graphs are unique except for n = 3k-1, 3k, 4k-2, or 4k-1. The value of ex(n,C_{2k+1}) can be read out from the works of Bondy, Woodall, and Bollobas, but here ...
Füredi, Zoltan, Gunderson, David S.
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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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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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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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Algorithms for minimum flows [PDF]
Computer Science Journal of Moldova, 2001 We present a generic preflow algorithm and several implementations of it, that solve the minimum flow problem in O(n2m) time.
Eleonor Ciurea, Laura Ciupal
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