Enviaments recents

  • Transformation and decomposition of clutters into matroids 

    Martí Farré, Jaume; Mier Vinué, Anna de (2017-05-25)
    Article
    Accés restringit per política de l'editorial
    A clutter is a family of mutually incomparable sets. The set of circuits of a matroid, its set of bases, and its set of hyperplanes are examples of clutters arising from matroids. In this paper we address the question of ...
  • Random subgraphs make identification affordable 

    Foucaud, Florent; Perarnau, Guillem; Serra Albó, Oriol (2017-01-02)
    Article
    Accés obert
    An identifying code of a graph is a dominating set which uniquely determines all the vertices by their neighborhood within the code. Whereas graphs with large minimum degree have small domination number, this is not the ...
  • On star forest ascending subgraph decomposition 

    Aroca Farrerons, José María; Lladó Sánchez, Ana M. (2017-02-03)
    Article
    Accés obert
    The Ascending Subgraph Decomposition (ASD) Conjecture asserts that every graph G with (n+12) edges admits an edge decomposition G=H1¿¿¿Hn such that Hi has i edges and it is isomorphic to a subgraph of Hi+1, i=1,…,n-1. We ...
  • Approximate results for rainbow labelings 

    Lladó Sánchez, Ana M.; Miller, Mirka (2017-03)
    Article
    Accés restringit per política de l'editorial
    A simple graph G=(V,E) is said to be antimagic if there exists a bijection f:E¿[1,|E|] such that the sum of the values of f on edges incident to a vertex takes different values on distinct vertices. The graph G is distance ...
  • Proinsulin protects against age-related cognitive loss through anti-inflammatory convergent pathways 

    Corpas, Ruben; Hernández Pinto, Alberto M.; Porquet, David; Hernández Sánchez, Catalina; Bosch, Fatima; Ortega Aznar, Arantxa; Comellas Padró, Francesc de Paula; de la Rosa, Enrique J.; Sanfeliu Pujol, Coral (2017-09-01)
    Article
    Accés restringit per política de l'editorial
    Brain inflammaging is increasingly considered as contributing to age-related cognitive loss and neurodegeneration. Despite intensive research in multiple models, no clinically effective pharmacological treatment has been ...
  • (Di)graph products, labelings and related results 

    López Masip, Susana Clara (2017-07)
    Article
    Accés restringit per política de l'editorial
    Gallian's survey shows that there is a big variety of labelings of graphs. By means of (di)graphs products we can establish strong relations among some of them. Moreover, due to the freedom of one of the factors, we can ...
  • On subsets of the normal rational curve 

    Ball, Simeon Michael; De Beule, Jan (2017-06-01)
    Article
    Accés restringit per política de l'editorial
    A normal rational curve of the (k-1) -dimensional projective space over Fq is an arc of size q+1 , since any k points of the curve span the whole space. In this paper, we will prove that if q is odd, then a subset of size ...
  • Counting configuration-free sets in groups 

    Rué Perna, Juan José; Serra Albó, Oriol; Vena Cros, Lluís (2017-01-01)
    Article
    Accés restringit per política de l'editorial
    © 2017 Elsevier Ltd. We provide asymptotic counting for the number of subsets of given size which are free of certain configurations in finite groups. Applications include sets without solutions to equations in non-abelian ...
  • Rainbow spanning subgraphs in bounded edge–colourings of graphs with large minimum degree 

    Cano Vila, María del Pilar; Perarnau Llobet, Guillem; Serra Albó, Oriol (2017-08-01)
    Article
    Accés restringit per política de l'editorial
    We study the existence of rainbow perfect matching and rainbow Hamiltonian cycles in edge–colored graphs where every color appears a bounded number of times. We derive asymptotically tight bounds on the minimum degree of ...
  • On sets defining few ordinary planes 

    Ball, Simeon Michael (2017-09-19)
    Article
    Accés restringit per política de l'editorial
    Let S be a set of n points in real three-dimensional space, no three collinear and not all co-planar. We prove that if the number of planes incident with exactly three points of S is less than (Formula presented.) for some ...
  • A generalisation of Sylvester's problem to higher dimensions 

    Ball, Simeon Michael; Monserrat, Joaquim (2017-07-01)
    Article
    Accés obert
    In this article we consider $S$ to be a set of points in $d$-space with the property that any $d$ points of $S$ span a hyperplane and not all the points of $S$ are contained in a hyperplane. The aim of this article is to ...
  • A finite version of the Kakeya problem 

    Ball, Simeon Michael; Blokhuis, Aart; Domenzain, Diego (2016-06-02)
    Article
    Accés obert
    Let $L$ be a set of lines of an affine space over a field and let $S$ be a set of points with the property that every line of $L$ is incident with at least $N$ points of $S$. Let $D$ be the set of directions of the lines ...

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