Results 21 to 30 of about 119,419 (266)
SHILLA GRAPHS WITH \(b=5\) AND \(b=6\)
Ural Mathematical Journal, 2021 A \(Q\)-polynomial Shilla graph with \(b = 5\) has intersection arrays \(\{105t,4(21t+1),16(t+1); 1,4 (t+1),84t\}\), \(t\in\{3,4,19\}\). The paper proves that distance-regular graphs with these intersection arrays do not exist.
Alexander A. Makhnev, Ivan N. Belousov
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Ars Mathematica Contemporanea, 2019 20 pages, 6 ...
Primoz Potocnik, Janos Vidali
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A Study of Regular and Irregular Neutrosophic Graphs with Real Life Applications
Mathematics, 2019 Fuzzy graph theory is a useful and well-known tool to model and solve many real-life optimization problems. Since real-life problems are often uncertain due to inconsistent and indeterminate information, it is very hard for an expert to model those ...
Liangsong Huang +5 more
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Nim-Regularity of Graphs [PDF]
The Electronic Journal of Combinatorics, 1999 Ehrenborg and Steingrímsson defined simplicial Nim, and defined Nim-regular complexes to be simplicial complexes for which simplicial Nim has a particular type of winning strategy. We completely characterize the Nim-regular graphs by the exclusion of two vertex-induced subgraphs, the graph on three vertices with one edge and the graph on five ...
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Regular divisor graph of finite commutative ring
Tikrit Journal of Pure Science, 2023 Let R be a finite commutative ring with identity 1. We introduce a new graph called regular divisor graph and denoted by . We classify the finite commutative ring to get a special graph and we are going to study some properties of this graph, clique ...
Payman Abbas Rashid, Hataw Saleem Rashid
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Journal of Combinatorial Theory, Series B, 1997 A covering projection from a graph \(G\) onto a graph \(H\) is a ``local isomorphism'': a mapping from the vertex set of \(G\) onto the vertex set of \(H\) such that, for every \(v\in V(G)\), the neighborhood of \(v\) is mapped bijectively onto the neighborhood (in \(H\)) of the image of \(v\).
Jan Kratochvíl +2 more
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A note on the problem of finding a (3,9)-cage
International Journal of Mathematics and Mathematical Sciences, 1985 In this paper, we discuss The poblem of finding a (3,9)-cage. A hamiltonian graph with girth 9 and 54 vertices is given. Except four vertices, each of the remaining vertices of this graph has valency Three.
P. K. Wong
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A Spectral Characterization of the S-Clique Extension of the Triangular Graphs
Discussiones Mathematicae Graph Theory, 2020 A regular graph is co-edge regular if there exists a constant µ such that any two distinct and non-adjacent vertices have exactly µ common neighbors. In this paper, we show that for integers s ≥ 2 and n large enough, any co-edge-regular graph which is ...
Tan Ying-Ying +2 more
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Graphs of intersections of closed polygonal chains
Журнал Белорусского государственного университета: Математика, информатика, 2021 In the paper such subclass of string graphs as intersection graphs of closed polygonal chains (class of CPC-graphs) was considered, necessary conditions for belonging to that class, forbidden subgraphs and operations with graphs which preserve belonging ...
Nikolai P. Prochorov, Ekaterina N. Dul
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Zero-sum flow number of categorical and strong product of graphs [PDF]
Transactions on Combinatorics, 2020 A zero-sum flow is an assignment of nonzero integers to the edges such that the sum of the values of all edges incident with each vertex is zero, and we call it a zero-sum $k$-flow if the absolute values of edges are less than $k$. We define the zero-sum
Muhammad Aamer Rashid +4 more
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