Ara es mostren els items 21-31 de 31

    • On t-cliques in k-walk-regular graphs 

      Dalfó Simó, Cristina; Fiol Mora, Miquel Àngel; Garriga Valle, Ernest (2009-08)
      Article
      Accés restringit per política de l'editorial
      A graph is walk-regular if the number of cycles of length rooted at a given vertex is a constant through all the vertices. For a walk-regular graph G with d+1 different eigenvalues and spectrally maximum diameter D = ...
    • On t-cliques in k-walk-regular graphs 

      Dalfó Simó, Cristina; Fiol Mora, Miquel Àngel; Garriga Valle, Ernest (Université de Bourdeaux, 2009)
      Text en actes de congrés
      Accés obert
    • 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 local spectra of the subconstituents of a vertex set and completely pseudo-regular codes 

      Cámara Vallejo, Marc; Fàbrega Canudas, José; Fiol Mora, Miquel Àngel; Garriga Valle, Ernest (2014-10-30)
      Article
      Accés restringit per política de l'editorial
      In this paper we study the relation between the local spectrum of a vertex set C and the local spectra of its subconstituents. In particular, it is shown that, when C is a completely regular code, such spectra are uniquely ...
    • Problemes de Càlcul II 

      Garriga Valle, Ernest; Prat Farran, Joana d'Arc; Ras Sabido, Antoni; Serra Albó, Oriol; Victoria Monge, Carlos (Universitat Politècnica de Catalunya, 2000)
      Apunts
      Accés obert
    • Some families of orthogonal polynomials of a discrete variable and their applications to graphs and codes 

      Fiol Mora, Miquel Àngel; Garriga Valle, Ernest; Fàbrega Canudas, José; Cámara Vallejo, Marc (2000-08)
      Article
      Accés obert
      We present some related families of orthogonal polynomials of a discrete variable and survey some of their applications in the study of (distance-regular) graphs and (completely regular) codes. One of the main peculiarities ...
    • The alternating and adjacency polynomials, and their relation with the spectra and diameters of graphs 

      Fiol Mora, Miquel Àngel; Garriga Valle, Ernest (Elsevier Science Publishers B. V., 1998-10)
      Article
      Accés obert
      Let Γ be a graph on n vertices, adjacency matrix A, and distinct eigenvalues λ > λ_1 > λ_2 > · · · > λ_d. For every k = 0,1, . . . ,d −1, the k-alternating polynomial P_k is defined to be the polynomial of degree k and norm |
    • The geometry of t-cliques in k-walk-regular graphs 

      Dalfó Simó, Cristina; Fiol Mora, Miquel Àngel; Garriga Valle, Ernest (2008-09)
      Article
      Accés obert
      A graph is walk-regular if the number of cycles of length $\ell$ rooted at a given vertex is a constant through all the vertices. For a walk-regular graph $G$ with $d+1$ different eigenvalues and spectrally maximum ...
    • The geometry of t-spreads in k-walk-regular graphs 

      Dalfó Simó, Cristina; Fiol Mora, Miquel Àngel; Garriga Valle, Ernest (Wiley InterScience, 2010-08)
      Article
      Accés obert
      A graph is walk-regular if the number of closed walks of length rooted at a given vertex is a constant through all the vertices for all . For a walk-regular graph G with d+1 different eigenvalues and spectrally maximum ...
    • When almost distance regularity attains distance regularity 

      Dalfó Simó, Cristina; Van Dam, Edwin; Fiol Mora, Miquel Àngel; Garriga Valle, Ernest (2010)
      Text en actes de congrés
      Accés restringit per política de l'editorial
    • When almost distance-regularity attains distance-regularity 

      Dalfó Simó, Cristina; Van Dam, Edwin; Fiol Mora, Miquel Àngel; Garriga Valle, Ernest (2010)
      Text en actes de congrés
      Accés obert
      Generally speaking, `almost distance-regular graphs' are graphs which share some, but not necessarily all, regularity properties that characterize distance-regular graphs. In this paper we rst propose four basic di erent ...