Ara es mostren els items 1-20 de 24

  • A solution to the tennis ball problem 

    Mier Vinué, Anna de; Noy Serrano, Marcos (2005)
    Article
    Accés obert
    We present a complete solution to the so-called tennis ball problem, which is equivalent to counting the number of lattice paths in the plane that use North and East steps and lie between certain boundaries. The solution ...
  • Bijections for Baxter families and related objects 

    Felsner, Stefan; Fusy, Éric; Noy Serrano, Marcos; Orden, David (2011-04)
    Article
    Accés obert
    The Baxter number can be written as $B_n = \sum_0^n \Theta_{k,n-k-1}$. These numbers have first appeared in the enumeration of so-called Baxter permutations; $B_n$ is the number of Baxter permutations of size $n$, and ...
  • Counting outerplanar maps 

    Geffner, I.; Noy Serrano, Marcos (2017-04-13)
    Article
    Accés obert
    A map is outerplanar if all its vertices lie in the outer face. We enumerate various classes of rooted outerplanar maps with respect to the number of edges and vertices. The proofs involve several bijections with lattice ...
  • Counting polygon dissections in the projective plane 

    Noy Serrano, Marcos; Rué Perna, Juan José (2008-10)
    Article
    Accés obert
    For each value of k ≥ 2, we determine the number pn of ways of dissecting a polygon in the projective plane into n subpolygons with k + 1 sides each. In particular, if k = 2 we recover a result of Edelman and Reiner (1997) ...
  • Disecciones de un polígono en el plano proyectivo 

    Noy Serrano, Marcos; Rué Perna, Juan José (Universidad de Valladolid, 2006)
    Comunicació de congrés
    Accés restringit per política de l'editorial
    En este trabajo obtenemos expresiones explícitas de las funciones generadoras de las triangulaciones y cuadrangulaciones del espacio topológico correspondiente a la supresión de un n-ágono del plano proyectivo real. En el ...
  • Enumeration of labeled 4-regular planar graphs 

    Noy Serrano, Marcos; Requile, Clement; Rué Perna, Juan José (2017-08-01)
    Article
    Accés obert
    In this extended abstract, we present the first combinatorial scheme for counting labeled 4-regular planar graphs through a complete recursive decomposition. More precisely, we show that the exponential generating function ...
  • Geometric tree graphs of points in convex position 

    Hernando Martín, María del Carmen; Hurtado Díaz, Fernando Alfredo; Márquez Pérez, Alberto; Mora Giné, Mercè; Noy Serrano, Marcos (1997)
    Article
    Accés obert
    Given a set $P$ of points in the plane, the geometric tree graph of $P$ is defined as the graph $T(P)$ whose vertices are non-crossing rectilinear spanning trees of $P$, and where two trees $T_1$ and $T_2$ are adjacent ...
  • Graph classes with given 3-connected components: asymptotic counting, limit laws and critical phenomena 

    Giménez Llach, Omer; Noy Serrano, Marcos; Rué Perna, Juan José (Edicions de la Universitat de Lleida (UdL), 2008)
    Comunicació de congrés
    Accés restringit per política de l'editorial
    Consider a family T of 3-connected graphs, and let G be the class of graphs whose 3-connected components are graphs in T . We present a general framework for analyzing such graphs classes based on singularity analysis of ...
  • Graphs of non-crossing perfect matchings 

    Hernando Martín, María del Carmen; Hurtado Díaz, Fernando Alfredo; Noy Serrano, Marcos (2001)
    Article
    Accés obert
    Let Pn be a set of n = 2m points that are the vertices of a convex polygon, and let Mm be the graph having as vertices all the perfect matchings in the point set Pn whose edges are straight line segments and do not cross, ...
  • Identities for non-crossing graphs and multigraphs 

    Albiol, Rubén; Noy Serrano, Marcos (2008-12)
    Article
    Accés restringit per política de l'editorial
    We refine an identity between the numbers of certain non-crossing graphs and multigraphs, by modifying a bijection found by P. Podbrdský [A bijective proof of an identity for noncrossing graphs, Discrete Math. 260 (2003) ...
  • Isolated cycles of critical random graphs 

    Noy Serrano, Marcos; Rasendrahasina, Vonjy; Ravelomanana, Vlady; Rué Perna, Juan José (Society for Industrial and Applied Mathematics (SIAM), 2017)
    Text en actes de congrés
    Accés obert
    Consider the Erdos-Renyi random graph G(n, M) built with n vertices and M edges uniformly randomly chosen from the set of n2 edges. Let L be a set of positive integers. For any number of edges M 6n/2 + O(n 2/3 ), we compute ...
  • On matroids determined by their Tutte polynomials 

    Mier Vinué, Anna de; Noy Serrano, Marcos (2005)
    Article
    Accés restringit per política de l'editorial
    A matroid is T-unique if it is determined up to isomorphism by its Tutte polynomial. Known T-unique matroids include projective and affine geometries of rank at least four, wheels, whirls, free and binary spikes, and certain ...
  • On the diameter of random planar graphs 

    Chapuy, G.; Fusy, Éric; Giménez Llach, Omer; Noy Serrano, Marcos (2015)
    Article
    Accés obert
    We show that the diameter diam(Gn) of a random labelled connected planar graph with n vertices is equal to n1/4+o(1) , in probability. More precisely, there exists a constant c > 0 such that {equation presented} for ˜ small ...
  • On the evaluation of the Tutte polynomial at the points (1,-1) and (2,-1) 

    Goodall, Andrew; Merino, Criel; Mier Vinué, Anna de; Noy Serrano, Marcos (2010)
    Text en actes de congrés
    Accés obert
    C. Merino proved recently the following identity between evaluations of the Tutte polynomial of complete graphs: t($K_{n+2}$; 1,−1) = t($K_n$;2,−1). In this work we extend this result by giving a large class of graphs with ...
  • On the maximum number of cycles in outerplanar and series-parallel graph 

    Mier Vinué, Anna de; Noy Serrano, Marcos (2009)
    Article
    Accés restringit per política de l'editorial
    Let c(n) be the maximum number of cycles in an outerplanar graph with n vertices. We show that lim $c(n)^{1/n}$ exists and equals β = 1.502837 . . ., where β is a constant related to the recurrence $x_n+1$=1+$x^2_n$, ...
  • On the number of labeled graphs of bounded treewidth 

    Baste, Julien; Noy Serrano, Marcos; Sau, Ignasi (2018-06-01)
    Article
    Accés restringit per política de l'editorial
    Let be Tnk the number of labeled graphs on vertices and treewidth at most (equivalently, the number o<f labeled partial -trees). We show that [...] for k>1 and some explicit absolute constant c>0. Disregarding terms depending ...
  • On the probability of planarity of a random graph near the critical point 

    Noy Serrano, Marcos; Ravelomanana, Vlady; Rue, Juanjo (2015-03-01)
    Article
    Accés obert
    Let G(n, M) be the uniform random graph with n vertices and M edges. Erdos and Renyi (1960) conjectured that the limiting probability; lim(n ->infinity) Pr{G(n, n/2) is planar}; exists and is a constant strictly between 0 ...
  • On zero-one and convergence laws for graphs embeddable on a fixed surface 

    Atserias, Albert; Kreutzer, Stephan; Noy Serrano, Marcos (Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2018)
    Text en actes de congrés
    Accés obert
    We show that for no surface except for the plane does monadic second-order logic (MSO) have a zero-one-law - and not even a convergence law - on the class of (connected) graphs embeddable on the surface. In addition we ...
  • Perspectivas en combinatoria 

    Noy Serrano, Marcos; Serra Albó, Oriol (Real Sociedad Matemática Española, 2016-10-03)
    Article
    Accés obert
  • Random cubic planar graphs revisited 

    Rué Perna, Juan José; Noy Serrano, Marcos; Requile, Clement (Elsevier, 2016)
    Altres
    Accés restringit per política de l'editorial
    The goal of our work is to analyze random cubic planar graphs according to the uniform distribution. More precisely, let G be the class of labelled cubic planar graphs and let gn be the number of graphs with n vertices. ...