Results 11 to 20 of about 834 (84)
A method to determine algebraically integral Cayley digraphs on finite Abelian group [PDF]
Researchers in the past have studied eigenvalues of Cayley digraphs or graphs. We are interested in characterizing Cayley digraphs on a finite Abelian group G whose eigenvalues are algebraic integers in a given number field K. And we succeed in finding a
Li, Fei
core +3 more sources
2-generated Cayley digraphs on nilpotent groups have hamiltonian paths [PDF]
Suppose G is a nilpotent, finite group. We show that if {a,b} is any 2-element generating set of G, then the corresponding Cayley digraph Cay(G;a,b) has a hamiltonian path.
Morris, Dave Witte
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Minimally Strong Subgraph (k,ℓ)-Arc-Connected Digraphs
Let D = (V,A) be a digraph of order n, S a subset of V of size k and 2 ≤ k ≤ n. A subdigraph H of D is called an S-strong subgraph if H is strong and S ⊆ V (H). Two S-strong subgraphs D1 and D2 are said to be arc-disjoint if A(D1) ∩ A(D2) = ∅.
Sun Yuefang, Jin Zemin
doaj +1 more source
The Second Neighbourhood for Bipartite Tournaments
Let T (X ∪ Y, A) be a bipartite tournament with partite sets X, Y and arc set A. For any vertex x ∈ X ∪Y, the second out-neighbourhood N++(x) of x is the set of all vertices with distance 2 from x.
Li Ruijuan, Sheng Bin
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The {−2,−1}-Selfdual and Decomposable Tournaments
We only consider finite tournaments. The dual of a tournament is obtained by reversing all the arcs. A tournament is selfdual if it is isomorphic to its dual.
Boudabbous Youssef, Ille Pierre
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On the n-Partite Tournaments with Exactly n − m + 1 Cycles of Length m
Gutin and Rafiey [Multipartite tournaments with small number of cycles, Australas J. Combin. 34 (2006) 17–21] raised the following two problems: (1) Let m ∈ {3, 4, . . ., n}.
Guo Qiaoping, Meng Wei
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The skew energy of random oriented graphs [PDF]
Given a graph $G$, let $G^\sigma$ be an oriented graph of $G$ with the orientation $\sigma$ and skew-adjacency matrix $S(G^\sigma)$. The skew energy of the oriented graph $G^\sigma$, denoted by $\mathcal{E}_S(G^\sigma)$, is defined as the sum of the ...
Chen, Xiaolin +2 more
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Outpaths of Arcs in Regular 3-Partite Tournaments
Guo [Outpaths in semicomplete multipartite digraphs, Discrete Appl. Math. 95 (1999) 273–277] proposed the concept of the outpath in digraphs. An outpath of a vertex x (an arc xy, respectively) in a digraph is a directed path starting at x (an arc xy ...
Guo Qiaoping, Meng Wei
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Background– Pseudomonas aeruginosa (PA) may cause suppurative otitis externa with severe inflammation and ulceration in dogs. Multidrug resistance is commonly reported for this organism, creating a difficult therapeutic challenge. Objective– The aim of this study was to evaluate the in vitro antimicrobial activity of a gel containing 0.5 µg/mL of ...
Giovanni Ghibaudo +6 more
wiley +1 more source
Conditional resolvability in graphs: a survey
For an ordered set W = {w1, w2, …, wk} of vertices and a vertex v in a connected graph G, the code of v with respect to W is the k‐vector cW(v) = (d(v, w1), d(v, w2), …, d(v, wk)), where d(x, y) represents the distance between the vertices x and y. The set W is a resolving set for G if distinct vertices of G have distinct codes with respect to W.
Varaporn Saenpholphat, Ping Zhang
wiley +1 more source

