Results 41 to 50 of about 116 (110)
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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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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Open Mathematics, 2018 The problem of structures learning in Bayesian networks is to discover a directed acyclic graph that in some sense is the best representation of the given database. Score-based learning algorithm is one of the important structure learning methods used to
Wang Jingyun, Liu Sanyang
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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
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On dynamic network security: A random decentering algorithm on graphs
Open Mathematics, 2018 Random Decentering Algorithm (RDA) on a undirected unweighted graph is defined and tested over several concrete scale-free networks. RDA introduces ancillary nodes to the given network following basic principles of minimal cost, density preservation ...
Trobajo M.T. +2 more
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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
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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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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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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
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Algorithmic aspects of bipartite graphs
International Journal of Mathematics and Mathematical Sciences, Volume 18, Issue 2, Page 299-304, 1995., 1995 We generalize previous work done by Donald J. Rose and Robert E. Tarjan [2], who developed efficient algorithms for use on directed graphs. This paper considers an edge elimination process on bipartite graphs, presenting several theorems which lead to an algorithm for computing the minimal fill‐in of a given ordered graph.
Mihály Bakonyi, Erik M. Varness
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