21 research outputs found

    Supermagic Generalized Double Graphs 1

    No full text
    A graph G is called supermagic if it admits a labelling of the edges by pairwise di erent consecutive integers such that the sum of the labels of the edges incident with a vertex is independent of the particular vertex. In this paper we will introduce some constructions of supermagic labellings of some graphs generalizing double graphs. Inter alia we show that the double graphs of regular Hamiltonian graphs and some circulant graphs are supermagic

    Some constructions of supermagic graphs using antimagic graphs

    Get PDF
    Abstract. AgraphG is called supermagic if it admits a labelling of the edges by pairwise different consecutive integers such that the sum of the labels of the edges incident with a vertex, the weight of vertex, is independent of the particular vertex. A graph G is called (a, 1)-antimagic if it admits a labelling of the edges by the integers {1,...,|E(G)|} such that the set of weights of the vertices consists of different consecutive integers. In this paper we will deal with the (a, 1)-antimagic graphs and their connection to the supermagic graphs. We will introduce three constructions of supermagic graphs using some (a, 1)-antimagic graphs

    Some results on the Hadwiger numbers of graphs

    Get PDF

    M_{2}-edge colorings of dense graphs

    No full text
    An edge coloring φ\varphi of a graph GG is called an Mi\mathrm{M}_i-edge coloring if φ(v)i|\varphi(v)|\leq i for every vertex vv of GG, where φ(v)\varphi(v) is the set of colors of edges incident with vv. Let Ki(G)\mathcal{K}_i(G) denote the maximum number of colors used in an Mi\mathrm{M}_i-edge coloring of GG. In this paper we establish some bounds of K2(G)\mathcal{K}_2(G), present some graphs achieving the bounds and determine exact values of K2(G)\mathcal{K}_2(G) for dense graphs

    Note on independent sets of a graph

    Get PDF
    summary:Let the number of kk-element sets of independent vertices and edges of a graph GG be denoted by n(G,k)n(G,k) and m(G,k)m(G,k), respectively. It is shown that the graphs whose every component is a circuit are the only graphs for which the equality n(G,k)=m(G,k)n(G,k)=m(G,k) is satisfied for all values of kk

    The Hadwiger number of complements of some graphs

    Get PDF
    corecore