Ara es mostren els items 1-14 de 14

    • Almost every tree with m edges decomposes K2m,2m 

      Drmota, Michael; Lladó Sánchez, Ana M. (2014-01)
      Article
      Accés obert
      We show that asymptotically almost surely a tree with m edges decomposes the complete bipartite graph K2m,2m, a result connected to a conjecture of Graham and Häggkvist. The result also implies that asymptotically almost ...
    • An interlacing approach for bounding the sum of Laplacian eigenvalues of graphs 

      Abiad, Aida; Fiol Mora, Miquel Àngel; Haemers, Willem H.; Perarnau Llobet, Guillem (2014)
      Text en actes de congrés
      Accés obert
      We apply eigenvalue interlacing techniques for obtaining lower and upper bounds for the sums of Laplacian eigenvalues of graphs, and characterize equality. This leads to generalizations of, and variations on theorems by ...
    • Approximate results for rainbow labelings 

      Lladó Sánchez, Ana M. (2015-04-14)
      Report de recerca
      Accés obert
    • Caracterizaciones combinatorias y algebraicas de grafos distancia-regulares 

      Fiol Mora, Miquel Àngel (Universitat Rovira i Virgili, 2014)
      Text en actes de congrés
      Accés obert
      Los grafos distancia-regulares aparecen a menudo en el estudio de es- tructuras matemáticas con un alto grado de simetría y/o regularidad. Un ejemplo bien conocido de tales grafos son los esqueletos ...
    • Connectivity: properties and structure 

      Balbuena Martínez, Maria Camino Teófila; Fàbrega Canudas, José; Fiol Mora, Miquel Àngel (CRC Press Taylor & Francis Group, 2013-12-05)
      Capítol de llibre
      Accés obert
      Connectivity is one of the central concepts of graph theory, from both a theoret- ical and a practical point of view. Its theoretical implications are mainly based on the existence of nice max-min characterization results, ...
    • Cycle codes of graphs and MDS array codes 

      Serra Albó, Oriol; Zemor, Gilles (2009-07-30)
      Article
      Accés restringit per política de l'editorial
      We investigate how to colour edges of graph so that any two colours make up a spanning tree. This problem is equivalent to transforming the cycle code of a graph into a Maximum Distance Separable (MDS) array code. Adopting ...
    • Decomposing almost complete graphs by random trees 

      Lladó Sánchez, Ana M. (2015-04-14)
      Report de recerca
      Accés obert
    • Decomposing almost complete graphs by random trees 

      Lladó Sánchez, Ana M. (2014)
      Text en actes de congrés
      Accés restringit per política de l'editorial
      An old conjecture of Ringel states that every tree with m edges decom- poses the complete graph K 2 m +1 . A more general version of the Ringel’s conjecture says that every tree with m edges decomposes K rm +1 for each r ...
    • Further topics in connectivity 

      Balbuena Martínez, Maria Camino Teófila; Fàbrega Canudas, José; Fiol Mora, Miquel Àngel (CRC Press Taylor & Francis Group, 2013-12-05)
      Capítol de llibre
      Accés obert
      Continuing the study of connectivity, initiated in §4.1 of the Handbook, we survey here some (sufficient) conditions under which a graph or digraph has a given connectivity or edge-connectivity. First, we describe results ...
    • On the algebraic theory of pseudo-distance-regulariry around a set 

      Fiol Mora, Miquel Àngel; Garriga Valle, Ernest (Elsevier, 1999-09)
      Article
      Accés restringit per política de l'editorial
      Let C be a connected graph with vertex set V, adjacency matrix A, positive eigenvector and corresponding eigenvalue 0. A natural generalization of distance-regularity around a vertex subset C V , which makes sense ...
    • On the generalitzed arc routing problem 

      Fernández Aréizaga, Elena (2013)
      Text en actes de congrés
      Accés obert
    • Some results on the structure of multipoles in the study of snarks 

      Fiol Mora, Miquel Àngel; Vilaltella Castanyer, Joan (2015-02-25)
      Article
      Accés obert
      Multipoles are the pieces we obtain by cutting some edges of a cubic graph in one or more points. As a result of the cut, a multipole M has vertices attached to a dangling edge with one free end, and isolated edges with ...
    • The Maximum degree of series-parallel graphs 

      Drmota, Michael; Giménez Llach, Omer; Noy Serrano, Marcos (2011-07)
      Article
      Accés restringit per acord de confidencialitat
      We prove that the maximum degree Δn of a random series-parallel graph with n vertices satisfies Δn/ log n → c in probability, and EΔn ∼ c log n for a computable constant c > 0. The same kind of result holds for 2-connected ...
    • Una fórmula explícita para obtener cuadrángulos generalizados y otros grafos pequeños de cintura 8 

      Abreu, M.; Balbuena Martínez, Maria Camino Teófila; Araujo Pardo, M. Gabriela; Labbate, D. (Universidad de Almería, 2011)
      Text en actes de congrés
      Accés obert
      Para cada potencia de primo q, se han constru do (q+1; 8)-jaulas como super cies cu adricas no degeneradas en 4-espacios proyectivos P(4; q). En primer lugar presentamos una construcci on de estos grafos de un modo ...