Results 21 to 30 of about 974 (99)
The Planar Index and Outerplanar Index of Some Graphs Associated to Commutative Rings
Discussiones Mathematicae - General Algebra and Applications, 2019 In this paper, we study the planar and outerplanar indices of some graphs associated to a commutative ring. We give a full characterization of these graphs with respect to their planar and outerplanar indices when R is a finite ring.
Barati Zahra, Afkhami Mojgan
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Veterinary Dermatology, Volume 27, Issue 5, Page 391-e98, October 2016., 2016 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
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Characteristic polynomials of some weighted graph bundles and its application to links
International Journal of Mathematics and Mathematical Sciences, Volume 17, Issue 3, Page 503-510, 1994., 1994 In this paper, we introduce weighted graph bundles and study their characteristic polynomial. In particular, we show that the characteristic polynomial of a weighted ‐bundles over a weighted graph G? can be expressed as a product of characteristic polynomials two weighted graphs whose underlying graphs are G As an application, we compute the signature ...
Moo Young Sohn, Jaeun Lee
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Improved Bounds for Some Facially Constrained Colorings
Discussiones Mathematicae Graph Theory, 2023 A facial-parity edge-coloring of a 2-edge-connected plane graph is a facially-proper edge-coloring in which every face is incident with zero or an odd number of edges of each color. A facial-parity vertex-coloring of a 2-connected plane graph is a proper
Štorgel Kenny
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Generalized Ramsey numbers for paths in 2‐chromatic graphs
International Journal of Mathematics and Mathematical Sciences, Volume 9, Issue 2, Page 273-276, 1986., 1985 Chung and Liu have defined the d‐chromatic Ramsey number as follows. Let 1 ≤ d ≤ c and let . Let 1, 2, …, t be the ordered subsets of d colors chosen from c distinct colors. Let G1, G2, …, Gt be graphs. The d‐chromatic Ramsey number denoted by is defined as the least number p such that, if the edges of the complete graph Kp are colored in any fashion ...
R. Meenakshi, P. S. Sundararaghavan
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The Crossing Numbers of Join of Some Graphs with n Isolated Vertices
Discussiones Mathematicae Graph Theory, 2018 There are only few results concerning crossing numbers of join of some graphs. In this paper, for some graphs on five vertices, we give the crossing numbers of its join with n isolated vertices.
Ding Zongpeng, Huang Yuanqiu
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The 4-girth-thickness of the complete multipartite graph
, 2019 The $g$-girth-thickness $\theta(g,G)$ of a graph $G$ is the smallest number of planar subgraphs of girth at least $g$ whose union is $G$. In this paper, we calculate the $4$-girth-thickness $\theta(4,G)$ of the complete $m$-partite graph $G$ when each ...
Rubio-Montiel, Christian
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Fundamental Cycles and Graph Embeddings
, 2008 In this paper we present a new Good Characterization of maximum genus of a graph which makes a common generalization of the works of Xuong, Liu, and Fu et al.
B. Mohar +10 more
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Facial [r,s,t]-Colorings of Plane Graphs
Discussiones Mathematicae Graph Theory, 2019 Let G be a plane graph. Two edges are facially adjacent in G if they are consecutive edges on the boundary walk of a face of G. Given nonnegative integers r, s, and t, a facial [r, s, t]-coloring of a plane graph G = (V,E) is a mapping f : V ∪ E → {1, . .
Czap Július +3 more
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Flippable Edges in Triangulations on Surfaces
Discussiones Mathematicae Graph Theory, 2022 Concerning diagonal flips on triangulations, Gao et al. showed that any triangulation G on the sphere with n ≥ 5 vertices has at least n − 2 flippable edges.
Ikegami Daiki, Nakamoto Atsuhiro
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