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Feedback Arc Number and Feedback Vertex Number of Cartesian Product of Directed Cycles
Discrete Dynamics in Nature and Society, Volume 2019, Issue 1, 2019., 2019 For a digraph D, the feedback vertex number τ(D), (resp. the feedback arc number τ′(D)) is the minimum number of vertices, (resp. arcs) whose removal leaves the resultant digraph free of directed cycles. In this note, we determine τ(D) and τ′(D) for the Cartesian product of directed cycles D=Cn1→□Cn2→□…Cnk→. Actually, it is shown that τ′D=n1n2…nk∑i=1k1/
Xiaohong Chen +2 more
wiley +1 more source
Discrete Mathematics & Theoretical Computer Science, 2004 A \emph(k,t)-track layout of a graph G consists of a (proper) vertex t-colouring of G, a total order of each vertex colour class, and a (non-proper) edge k-colouring such that between each pair of colour classes no two monochromatic edges cross.
Vida Dujmović +2 more
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On the Relationships between Zero Forcing Numbers and Certain Graph Coverings
Special Matrices, 2014 The zero forcing number and the positive zero forcing number of a graph are two graph parameters that arise from two types of graph colourings. The zero forcing number is an upper bound on the minimum number of induced paths in the graph that cover all ...
Taklimi Fatemeh Alinaghipour +2 more
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On vertex‐transitive graphs with a unique hamiltonian cycle
Journal of Graph Theory, Volume 108, Issue 1, Page 65-99, January 2025.Abstract A graph is said to be uniquely hamiltonian if it has a unique hamiltonian cycle. For a natural extension of this concept to infinite graphs, we find all uniquely hamiltonian vertex‐transitive graphs with finitely many ends, and also discuss some examples with infinitely many ends.
Babak Miraftab, Dave Witte Morris
wiley +1 more source
Outerplanar Partitions of Planar Graphs
Journal of Combinatorial Theory, Series B, 1996 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
openaire +3 more sources
On the Hub Number of Ring Graphs and Their Behavior Under Graph Operations
International Journal of Mathematics and Mathematical Sciences, Volume 2025, Issue 1, 2025.This study examines the hub number of ring graphs and investigates their behavior under operations such as union, intersection, and join. Different findings for this parameter are found for a variety of types of ring graphs, such as commutative ring graphs, path ring graphs, complete ring graphs, cycle ring graphs, and star ring graphs, for which the ...
Mohammed Alsharafi +3 more
wiley +1 more source
A graph and its complement with specified properties I: connectivity
International Journal of Mathematics and Mathematical Sciences, 1979 We investigate the conditions under which both a graph G and its complement G¯ possess a specified property. In particular, we characterize all graphs G for which G and G¯ both (a) have connectivity one, (b) have line-connectivity one, (c) are 2 ...
Jin Akiyama, Frank Harary
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On the Geometric Ramsey Number of Outerplanar Graphs
, 2013 We prove polynomial upper bounds of geometric Ramsey numbers of pathwidth-2 outerplanar triangulations in both convex and general cases. We also prove that the geometric Ramsey numbers of the ladder graph on $2n$ vertices are bounded by $O(n^{3})$ and $O(
Cibulka, Josef +4 more
core +1 more source
Minimal Cycle Bases of Outerplanar Graphs [PDF]
The Electronic Journal of Combinatorics, 1998 2-connected outerplanar graphs have a unique minimal cycle basis with length $2\vert E\vert-\vert V\vert$. They are the only Hamiltonian graphs with a cycle basis of this length.
Leydold, Josef, Stadler, Peter F.
openaire +6 more sources
Self‐avoiding walks and polygons on hyperbolic graphs
Journal of Graph Theory, Volume 106, Issue 3, Page 435-473, July 2024.Abstract We prove that for the d $d$‐regular tessellations of the hyperbolic plane by k $k$‐gons, there are exponentially more self‐avoiding walks of length n $n$ than there are self‐avoiding polygons of length n $n$. We then prove that this property implies that the self‐avoiding walk is ballistic, even on an arbitrary vertex‐transitive graph ...
Christoforos Panagiotis
wiley +1 more source