Results 31 to 40 of about 1,099 (89)
On the Metric Dimension of Directed and Undirected Circulant Graphs
Discussiones Mathematicae Graph Theory, 2020 The undirected circulant graph Cn(±1, ±2, . . . , ±t) consists of vertices v0, v1, . . . , vn−1 and undirected edges vivi+j, where 0 ≤ i ≤ n − 1, 1 ≤ j ≤ t (2 ≤ t ≤ n2{n \over 2} ), and the directed circulant graph Cn(1, t) consists of vertices v0, v1, .
Vetrík Tomáš
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Journal of Mathematics, Volume 2025, Issue 1, 2025.In its crystalline state, the α‐icosahedral nanosheet of boron demonstrates superconductivity and thermal electronic properties. Mathematical research on a graph’s structure yields a graph descriptor, a numerical measure. Chemical graph theory employs connectivity descriptors to analyze molecular structures, providing crucial insights into many ...
Khalil Hadi Hakami +3 more
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On the cycle structure of hamiltonian k-regular bipartite graphs of order 4k [PDF]
, 2009 It is shown that a hamiltonian $n/2$-regular bipartite graph $G$ of order $2n>8$ contains a cycle of length $2n-2$. Moreover, if such a cycle can be chosen to omit a pair of adjacent vertices, then $G$ is bipancyclic.Comment: 3 ...
Adamus, Janusz
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Closed and asymptotic formulas for energy of some circulant graphs
, 2016 We consider circulant graphs G(r,N) where the vertices are the integers modulo N and the neighbours of 0 are {-r,...,-1,1,...,r}. The energy of G(r,N) is a trigonometric sum of N*r terms. For low values of r we compute this sum explicitly.
Arango, Carlos Alberto Marín +1 more
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, 1997 Let S_m denote the m-vertex simple digraph formed by m-1 edges with a common tail. Let f(m) denote the minimum n such that every n-vertex tournament has a spanning subgraph consisting of n/m disjoint copies of S_m. We prove that m lg m - m lg lg m
Chen, Guantao +2 more
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Gaps in the Saturation Spectrum of Trees
Discussiones Mathematicae Graph Theory, 2019 A graph G is H-saturated if H is not a subgraph of G but the addition of any edge from the complement of G to G results in a copy of H. The minimum number of edges (the size) of an H-saturated graph on n vertices is denoted sat(n,H), while the maximum ...
Horn Paul +3 more
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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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Note on minimally $k$-rainbow connected graphs [PDF]
, 2012 An edge-colored graph $G$, where adjacent edges may have the same color, is {\it rainbow connected} if every two vertices of $G$ are connected by a path whose edge has distinct colors.
Li, Hengzhe +3 more
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The Degree-Diameter Problem for Outerplanar Graphs
Discussiones Mathematicae Graph Theory, 2017 For positive integers Δ and D we define nΔ,D to be the largest number of vertices in an outerplanar graph of given maximum degree Δ and diameter D. We prove that nΔ,D=ΔD2+O (ΔD2−1)$n_{\Delta ,D} = \Delta ^{{D \over 2}} + O\left( {\Delta ^{{D \over 2 ...
Dankelmann Peter +2 more
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Avoiding rainbow 2-connected subgraphs
Open Mathematics, 2017 While defining the anti-Ramsey number Erdős, Simonovits and Sós mentioned that the extremal colorings may not be unique. In the paper we discuss the uniqueness of the colorings, generalize the idea of their construction and show how to use it to ...
Gorgol Izolda
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