Abstract
For any vertex x in a connected graph G of order n ≥ 2, a set S x ⊆ V (G) is an x-detour monophonic set of G if each vertex v ∈ V (G) lies on an x-y detour monophonic path for some element y in S x . The minimum cardinality of an x-detour monophonic set of G is the x-detour monophonic number of G, denoted by dm x (G). A connected x-detour monophonic set of G is an x-detour monophonic set S x such that the subgraph induced by S x is connected. The minimum cardinality of a connected x-detour monophonic set of G is the connected x-detour monophonic number of G, denoted by cdm x (G). A connected x-detour monophonic set S x of G is called a minimal connected x-detour monophonic set if no proper subset of S x is a connected x-detour monophonic set. The upper connected x-detour monophonic number of G, denoted by cdm+ x (G), is defined to be the maximum cardinality of a minimal connected x-detour monophonic set of G. We determine bounds and exact values of these parameters for some special classes of graphs. We also prove that for positive integers r,d and k with 2 ≤ r ≤ d and k ≥ 2, there exists a connected graph G with monophonic radius r, monophonic diameter d and upper connected x-detour monophonic number k for some vertex x in G. Also, it is shown that for positive integers j,k,l and n with 2 ≤ j ≤ k ≤ l ≤ n - 3, there exists a connected graph G of order n with dm x (G) = j,dm+ x (G) = k and cdm+ x (G) = l for some vertex x in G.
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References
F. Buckley and F. Harary, Distance in graphs, Addison-Wesley, Redwood City, CA, (1990).
F. Buckley, F. Harary and L. U. Quintas, Extremal results on the geodetic number of a graph, Scientia, A2 (1988), 17–26.
G. Chartrand, H. Escuadro and P. Zhang, Detour distance in graphs, J. Combin. Math. Combin. Comput., 53 (2005), 75–94.
G. Chartrand, F. Harary and P. Zhang, On the geodetic number of a graph, Networks, 39(1) (2002), 1–6.
G. Chartrand, F. Harary, H. C. Swart and P. Zhang, Geodomination in graphs, Bull. Inst. Combin. Appl., 31 (2001), 51–59.
G. Chartrand, G. L. Johns and P. Zhang, Detour number of a graph, Util. Math., 64 (2003), 97–113.
F. Harary, Graph theory, Addison-Wesley (1969).
F. Harary, E. Loukakis and C. Tsouros, The geodetic number of a graph, Math. Comput. Modeling, 17(11) (1993), 87–95.
A. P. Santhakumaran and P. Titus, Vertex geodomination in graphs, Bulletin of Kerala Mathematics Association, 2(2) (2005), 45–57.
A. P. Santhakumaran and P. Titus, On the vertex geodomination number of a graph, Ars Combin., 101 (2011), 137–151.
A. P. Santhakumaran and P. Titus, Monophonic distance in graphs, Discrete Math., Alg. and Appl., 3(2) (2011), 159–169.
A. P. Santhakumaran and P. Titus, A note on monophonic distance in graphs, Discrete Math., Alg. and Appl., 4(2) (2012), 1250018-(5 pages).
P. Titus and P. Balakrishnan, The vertex detour monophonic number of a graph, (Communicated).
P. Titus and P. Balakrishnan, The upper vertex detour monophonic number of a graph, Ars Combin., (To appear).
P. Titus and P. Balakrishnan, The connected vertex detour monophonic number of a graph, (Communicated).
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Also at Department of Computer Science, Liverpool Hope University, Liverpool, UK; Department of Computer Science, Ball State University, USA.
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Arumugam, S., Balakrishnan, P., Santhakumaran, A.P. et al. The Upper Connected Vertex Detour Monophonic Number of a Graph. Indian J Pure Appl Math 49, 365–379 (2018). https://doi.org/10.1007/s13226-018-0274-7
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DOI: https://doi.org/10.1007/s13226-018-0274-7