Results 41 to 50 of about 91 (88)
Interval-Valued Fuzzy Soft Graphs
Topological Algebra and its Applications, 2017 In this paper, we combine concepts of interval-valued fuzzy soft sets and graph theory. Then we introduce notations of interval-valued fuzzy soft graphs and complete interval-valued fuzzy soft graphs.
Zihni Onur +2 more
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Mixing Times of Markov Chains on Degree Constrained Orientations of Planar Graphs [PDF]
Discrete Mathematics & Theoretical Computer Science, 2017 We study Markov chains for $\alpha$-orientations of plane graphs, these are orientations where the outdegree of each vertex is prescribed by the value of a given function $\alpha$.
Stefan Felsner, Daniel Heldt
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Bounds for the smallest $k$-chromatic graphs of given girth [PDF]
Discrete Mathematics & Theoretical Computer Science, 2019 Let $n_g(k)$ denote the smallest order of a $k$-chromatic graph of girth at least $g$. We consider the problem of determining $n_g(k)$ for small values of $k$ and $g$.
Geoffrey Exoo, Jan Goedgebeur
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Structural Properties of Recursively Partitionable Graphs with Connectivity 2
Discussiones Mathematicae Graph Theory, 2017 A connected graph G is said to be arbitrarily partitionable (AP for short) if for every partition (n1, . . . , np) of |V (G)| there exists a partition (V1, . . . , Vp) of V (G) such that each Vi induces a connected subgraph of G on ni vertices.
Baudon Olivier +3 more
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Lower and upper bounds of shortest paths in reachability graphs
International Journal of Mathematics and Mathematical Sciences, Volume 2004, Issue 57, Page 3023-3036, 2004., 2004 We prove the following property for safe marked graphs, safe conflict‐free Petri nets, and live and safe extended free‐choice Petri nets. We prove the following three results. If the Petri net is a marked graph, then the length of the shortest path is at most (|T| − 1) · |T|/2.
P. K. Mishra
wiley +1 more source
The agreement distance of unrooted phylogenetic networks [PDF]
Discrete Mathematics & Theoretical Computer Science, 2020 A rearrangement operation makes a small graph-theoretical change to a phylogenetic network to transform it into another one. For unrooted phylogenetic trees and networks, popular rearrangement operations are tree bisection and reconnection (TBR) and ...
Jonathan Klawitter
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International Journal of Mathematics and Mathematical Sciences, Volume 26, Issue 11, Page 679-684, 2001., 2001 For an arbitrary undirected graph G, we are designing a logical model for the Hamiltonian Cycle Problem (HCP), using tools of Boolean algebra only. The obtained model is a logic formulation of the conditions for the existence of the Hamiltonian cycle, and uses m Boolean variables, where m is the number of the edges of a graph.
Anatoly D. Plotnikov
wiley +1 more source
On characteristic and permanent polynomials of a matrix
Special Matrices, 2017 There is a digraph corresponding to every square matrix over ℂ. We generate a recurrence relation using the Laplace expansion to calculate the characteristic and the permanent polynomials of a square matrix.
Singh Ranveer, Bapat R. B.
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Long cycles in certain graphs of large degree
International Journal of Mathematics and Mathematical Sciences, Volume 24, Issue 10, Page 691-697, 2000., 2000 Let G be a connected graph of order n and X = {x ∈ V : d(x) ≥ n/2}. Suppose |X| ≥ 3 and G satisfies the modified Fan′s condition. We show that the vertices of the block B of G containing X form a cycle. This generalizes a result of Fan. We also give an efficient algorithm to obtain such a cycle. The complexity of this algorithm is O(n2). In case G is 2‐
Pak-Ken Wong
wiley +1 more source
Path-induced closure operators on graphs for defining digital Jordan surfaces
Open Mathematics, 2019 Given a simple graph with the vertex set X, we discuss a closure operator on X induced by a set of paths with identical lengths in the graph. We introduce a certain set of paths of the same length in the 2-adjacency graph on the digital line ℤ and ...
Šlapal Josef
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