Results 51 to 60 of about 92,304 (328)
Discrete Applied Mathematics, 2010 this paper has been withdrawn because it has been ...
Mekkia Kouider, Siham Bekkai
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On the acyclic disconnection and the girth
Discrete Applied Mathematics, 2015 The acyclic disconnection, (omega) over right arrow (D), of a digraph D is the maximum number of connected components of the underlying graph of D - A(D*), where D* is an acyclic subdigraph of D. We prove that (omega) over right arrow (D) >= g - 1 for every strongly connected digraph with girth g >= 4, and we show that (omega) over right arrow (D) = g -
Balbuena Martínez, Maria Camino Teófila +1 more
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Bulletin of the London Mathematical Society, 2019 To appear in Bull.
Liebeck, M, Shalev, A
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Large-Girth Roots of Graphs [PDF]
SIAM Journal on Discrete Mathematics, 2010 14 pages, 4 ...
Adamaszek, Anna, Adamaszek, Michal
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Number of cycles of small length in a graph
AKCE International Journal of Graphs and Combinatorics, 2023 Let G be a simple undirected graph. In this article, we obtain an explicit formula for the number of 8-cycles in G in terms of the entries of its adjacency matrix. We provide new formulae to find the number of cycles of length 4, 5 and 6 in G.
Sasmita Barik, Sane Umesh Reddy
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High Girth Hypergraphs with Unavoidable Monochromatic or Rainbow Edges
Discussiones Mathematicae Graph Theory, 2022 A classical result of Erdős and Hajnal claims that for any integers k, r, g ≥ 2 there is an r-uniform hypergraph of girth at least g with chromatic number at least k.
Axenovich Maria, Karrer Annette
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On General Reduced Second Zagreb Index of Graphs
Mathematics, 2022 Graph-based molecular structure descriptors (often called “topological indices”) are useful for modeling the physical and chemical properties of molecules, designing pharmacologically active compounds, detecting environmentally hazardous substances, etc.
Lkhagva Buyantogtokh +2 more
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Some Spectral and Quasi-Spectral Characterizations of Distance-Regular Graphs [PDF]
, 2016 In this paper we consider the concept of preintersection numbers of a graph. These numbers are determined by the spectrum of the adjacency matrix of the graph, and generalize the intersection numbers of a distance-regular graph.
Abiad, A., Fiol, M. A., van Dam, E. R.
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Discrete Mathematics, 2000 AbstractIt was conjectured by Caccetta and Häggkvist in 1978 that the girth of every digraph with n vertices and minimum outdegree r is at most ⌈n/r⌉. The conjecture was proved for r=2 by Caccetta and Häggkvist, for r=3 by Hamidoune and for r=4,5 by Hoáng and Reed.
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Dairy, 2022 Selection pressure for greater milk solid production, calving ease and early puberty attainment has resulted in the alteration of the growth trajectory of New Zealand dairy heifers.
Michaela J. Gibson +5 more
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