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Mostrando ítems 31-40 de 65
Artículo
Rebuilding convex sets in graphs
(2005)
The usual distance between pairs of vertices in a graph naturally gives rise to the notion of an interval between a pair of vertices in a graph. This in turn allows us to extend the notions of convex sets, convex hull, and ...
Artículo
Moore spaces in proper homotopy
(University of Tsukuba, 1995)
Moore spaces are de ned in proper homotopy theory. Some results on the existence and uniqueness of those spaces are proven. An example of two non properly equivalent Moore spaces is given.
Artículo
Monochromatic geometric k-factors in red-blue sets with white and Steiner points
(2009)
We study the existence of monochromatic planar geometric k-factors on sets of red and blue points. When it is not possible to find a k-factor we make use of auxiliary points: white points, whose position is given as a datum ...
Artículo
An aperiodic tiles machine
(2002)
The results we introduce in this work lead to get an algorithm which produces aperiodic sets of tiles using Voronoi diagrams. This algorithm runs in optimal worst-case time O(nlogn). Since a wide range of new examples can ...
Artículo
New results on the robust coloring problem
(Springer, 2024-03-23)
Many variations of the classical graph coloring model have been intensively studied due to their multiple applications; scheduling problems and aircraft assignments, for instance, motivate the robust coloring problem. This ...
Artículo
Geometric Realization of Möbius Triangulations
(2008)
A Möbius triangulation is a triangulation on the Möbius band. A geometric realization of a map M on a surface $\Sigma$ is an embedding of $\Sigma$ into a Euclidean 3-space $\mathbb{R}^3$ such that each face of M is a flat ...
Artículo
Computing the Tutte polynomial of Archimedean tilings
(2014)
We describe an algorithm to compute the Tutte polynomial of large fragments of Archimedean tilings by squares, triangles, hexagons and combinations thereof. Our algorithm improves a well known method for computing the Tutte ...
Artículo
On infinite outerplanar graphs
(Institute of Mathematics of the Czech Academy of Sciences, 1994)
In this Note, we study infinite graphs with locally finite outerplane embeddings, given a characterization by forbidden subgraphs
Artículo
Miscellaneous properties of embeddings of line, total and middle graphs
(2001)
Chartrand et al. (J. Combin. Theory Ser. B 10 (1971) 12–41) proved that the line graph of a graph G is outerplanar if and only if the total graph of G is planar. In this paper, we prove that these two conditions are ...
Artículo
Extremal Graphs without Topological Complete Subgraphs
(2004)
The exact values of the function $ex(n;TK_{p})$ are known for ${\lceil \frac{2n+5}{3}\rceil}\leq p < n$ (see [Cera, Diánez, and Márquez, SIAM J. Discrete Math., 13 (2000), pp. 295--301]), where $ex(n;TK_p)$ is the maximum ...