Now showing items 1-7 of 7

  • A sufficient condition for Pk-path graphs being r-connected 

    Balbuena Martínez, Maria Camino Teófila; García-Vázquez, Pedro (2007-08)
    Article
    Open Access
    Given an integer k≥1 and any graph G; the path graph $P_k(G)$ has for vertices the paths of length k in G, and two vertices are joined by an edge if and only if the intersection of the corresponding paths forms a path of ...
  • On the connectivity and restricted edge-connectivity of 3-arc graphs 

    Balbuena Martínez, Maria Camino Teófila; García-Vázquez, Pedro (Iniciativa Digital Politècnica, 2011)
    Conference report
    Open Access
    A 3−arc of a graph G is a 4-tuple (y, a, b, x) of vertices such that both (y, a, b) and (a, b, x) are paths of length two in G. Let ←→G denote the symmetric digraph of a graph G. The 3-arc graph X(G) of a given graph G is ...
  • On the restricted arc-connectivity of s-geodetic digraphs 

    Balbuena Martínez, Maria Camino Teófila; García-Vázquez, Pedro (2010-10)
    Article
    Restricted access - publisher's policy
    For a strongly connected digraph D the restricted arc-connectivity λ′(D) is defined as the minimum cardinality of an arc-cut over all arc-cuts S satisfying that D - S has a non-trivial strong component D₁ such that D-V ...
  • On the vulnerability of some families of graphs 

    Moreno Casablanca, Rocío; Díanez, Ana R.; García-Vázquez, Pedro (Iniciativa Digital Politècnica, 2011)
    Conference report
    Open Access
    The toughness of a noncomplete graph G is defined as τ (G) = min{|S|/ω(G − S)}, where the minimum is taken over all cutsets S of vertices of G and ω(G − S) denotes the number of components of the resultant graph G − S by ...
  • On the λ'-optimality of s-geodetic digraphs 

    Balbuena Martínez, Maria Camino Teófila; García-Vázquez, Pedro (Iniciativa Digital Politècnica, 2011)
    Conference report
    Open Access
    For a strongly connected digraph D the restricted arc-connectivity λ'(D) is defined as the minimum cardinality of an arc-cut over all arc-cuts S satisfying that D − S has a non trivial strong component D1 such that D − V ...
  • Subdivisions in a bipartite graph 

    Balbuena Martínez, Maria Camino Teófila; Cera, Martín; García-Vázquez, Pedro; Valenzuela, Juan Carlos (Iniciativa Digital Politècnica, 2011)
    Conference report
    Open Access
    Given a bipartite graph G with m and n vertices, respectively,in its vertices classes, and given two integers s, t such that 2 ≤ s ≤ t, 0 ≤ m−s ≤ n−t, and m+n ≤ 2s+t−1, we prove that if G has at least mn−(2(m−s)+n−t) edges ...
  • Superconnectivity of graphs with odd girth g and even girth h 

    Montejano, Luis P.; Balbuena Martínez, Maria Camino Teófila; García-Vázquez, Pedro (2009-09)
    Conference report
    Restricted access - publisher's policy
    A maximally connected graph G of minimum degree δ is said to be superconnected (for short super-κ) if all disconnecting sets of cardinality δ are the neighborhood of some vertex of degree δ. Sufficient conditions on the ...