Now showing items 1-20 of 29

    • A new labeling construction from the ⊗h-product 

      López Masip, Susana-Clara; Muntaner Batle, Francesc Antoni; Prabu, M. (Elsevier, 2017)
      The -product that is referred in the title was introduced in 2008 as a generalization of the Kronecker product of digraphs. Many relations among labelings have been obtained since then, always using as a second factor a ...
    • A problem on edge-magic labelings of cycles 

      López Masip, Susana-Clara; Muntaner Batle, Francesc Antoni; Rius Font, Miquel (Cambridge University Press, 2014-06-14)
      Kotzig and Rosa defined in 1970 the concept of edge-magic labelings as follows: let G be a simple (p, q)-graph (that is, a graph of order p and size q without loops or multiple edges). A bijective function f : V (G)∪E(G) ...
    • Bi-magic and other generalizations of super edge-magic labelings 

      López Masip, Susana-Clara; Muntaner Batle, Francesc Antoni; Rius Font, Miquel (Cambridge University Press, 2011)
      In this paper, we use the product ⊗h in order to study super edge-magic labelings, bi-magic labelings and optimal k-equitable labelings. We establish, with the help of the product ⊗h, new relations between super edge-magic ...
    • Connectivity and other invariants of generalized products of graphs 

      López Masip, Susana-Clara; Muntaner Batle, Francesc Antoni (Springer, 2015)
      Figueroa-Centeno et al. [4] introduced the following product of digraphs let D be a digraph and let Γ be a family of digraphs such that V (F) = V for every F∈Γ . Consider any function h:E(D)→Γ . Then the product D⊗hΓ is ...
    • (Di)graph decompositions and magic type labelings: a dual relation 

      López Masip, Susana-Clara; Muntaner Batle, Francesc Antoni; Prabu, M. (Springer, 2020-10)
      A graph G is called edge-magic if there is a bijective function f from the set of vertices and edges to the set {1, 2, . . . , |V (G)| + |E(G)|} such that the sum f(x) + f(xy) + f(y) for any xy in E(G) is constant. Such ...
    • (Di)graph products, labelings and related results 

      López Masip, Susana-Clara (Elsevier, 2017)
      Gallian's survey shows that there is a big variety of labelings of graphs. By means of (di)graphs products we can establish strong relations among some of them. Moreover, due to the freedom of one of the factors, we can ...
    • Distance labelings: a generalization of Langford sequences 

      López Masip, Susana-Clara; Muntaner Batle, Francesc Antoni (University of Primorska, 2017)
      A Langford sequence of order m and defect d can be identified with a labeling of the vertices of a path of order 2m in which each label from d up to d + m − 1 appears twice and in which the vertices that have been labeled ...
    • Distance-based topological polynomials associated with zero-divisor graphs 

      Ahmad, Ali; López Masip, Susana-Clara (Hindawi, 2021-05)
      Let R be a commutative ring with nonzero identity and let Z(R) be its set of zero divisors. The zero-divisor graph of R is the graph T(R) with vertex set V(T(R))=Z(R)*, where Z(R)*=Z(R)\{0} , and edge set E(T(R))={{x,y}:x·y=0} ...
    • Enumerating super edge-magic labelings for some types of path-like trees 

      López Masip, Susana-Clara; Muntaner Batle, Francesc Antoni; Rius Font, Miquel (University of Manitoba, 2015)
      The main goal of this paper is to use a variation of the Kronecker product of matrices in order to obtain lower bounds for the number of non isomorphic super edge-magic labelings of some types of pathlike trees. As a ...
    • Enumerating super edge-magic labelings for the union of nonisomorphic graphs 

      Ahmad, Ali; López Masip, Susana-Clara; Muntaner Batle, Francesc Antoni; Rius Font, Miquel (Cambridge University Press, 2011)
      A super edge-magic labeling of a graph G=(V,E) of order p and size q is a bijection f:V ∪E→{i}p+qi=1 such that: (1) f(u)+f(uv)+f(v)=k for all uv∈E; and (2) f(V )={i}pi=1. Furthermore, when G is a linear forest, the super ...
    • Every tree is a large subtree of a tree that decomposes Kn or Kn,n 

      Lladó, Anna; López Masip, Susana-Clara; Moragas, J. (Elsevier, 2010)
      Let T be a tree with m edges. A well-known conjecture of Ringel states that every tree T with m edges decomposes the complete graph K2m+1. Graham and H¨aggkvist conjectured that T also decomposes the complete bipartite ...
    • Labeling constructions using digraph products 

      López Masip, Susana-Clara; Muntaner Batle, Francesc Antoni; Rius Font, Miquel (Elsevier, 2013)
      In this paper we study the edge-magicness of graphs with equal size and order, and we use such graphs and digraph products in order to construct labelings of different classes and of different graphs. We also study super ...
    • Langford sequences and a product of digraphs 

      López Masip, Susana-Clara; Muntaner Batle, Francesc Antoni (Elsevier, 2016)
      Skolem and Langford sequences and their many generalizations have applications in numerous areas. The -product is a generalization of the direct product of digraphs. In this paper we use the -product and super edge-magic ...
    • Large restricted sumsets in general Abelian groups 

      Hamidoune, Yahya Ould; López Masip, Susana-Clara; Plagne, Alain (Elsevier, 2013)
      Let A, B and S be subsets of a finite Abelian group G. The restricted sumset of A and B with respect to S is defined as A ∧S B = {a + b : a ∈ A, b ∈ B and a − b /∈ S}. Let LS = maxz∈G |{(x, y) : x, y ∈ G, x + y = z and x ...
    • Magic coverings and the Kronecker product 

      López Masip, Susana-Clara; Muntaner Batle, Francesc Antoni; Rius Font, Miquel (2014)
      In this paper we study a relationship existing among (super) magic coverings and the well known Kronecker product of matrices. We also introduce the concept of Zn-property for digraphs in order to study this relation ...
    • Minimum tree decompositions with a given tree as a factor 

      Lladó, Anna; López Masip, Susana-Clara (Combinatorial Mathematics Society of Australasia, 2005)
      A tree decomposition of a graph G is a family of subtrees whose sets of edges partition the set of edges of G. In this paper we are interested in the structure of the trees involved in tree decompositions with the minimum ...
    • New constructions for the n-queens problem 

      Bača, Martin; López Masip, Susana-Clara; Muntaner Batle, Francesc Antoni; Semaničová-Feňovčíková, Andrea (Springer, 2020-02)
      Let D be a digraph, possibly with loops. A queen labeling of D is a bijective function l:V(G)⟶{1,2,…,|V(G)|} such that, for every pair of arcs in E(D), namely (u, v) and (u′,v′) we have (i) l(u)+l(v)≠l(u′)+l(v′) and (ii) ...
    • New problems related to the valences of (super) edge-magic labelings 

      López Masip, Susana-Clara; Muntaner Batle, Francesc Antoni; Rius Font, Miquel (2013)
      A graph G of order p and size q is edge-magic if there is a bijective function f : V (G) ∪ E(G) −→ {i} p+q i=1 such that f(x) + f(xy) + f(y) = k , for all xy ∈ E(G) . The function f is an edge-magic labeling of G and the ...
    • On super edge-magic decomposable graphs 

      López Masip, Susana-Clara; Muntaner Batle, Francesc Antoni; Rius Font, Miquel (Springer, 2012)
      Let G be any graph and let {Hi}i∈I be a family of graphs such that E(Hi) ∩ E(Hj ) = ∅ when i 6= j, ∪i∈IE(Hi) = E(G) and E(Hi) 6= ∅ for all i ∈ I. In this paper we introduce the concept of {Hi}i∈I -super edge-magic decomposable ...
    • On the beta-number of forests with isomorphic components 

      Ichishima, R.; López Masip, Susana-Clara; Muntaner Batle, Francesc Antoni; Oshima, A. (De Gruyter Open, 2018)
      The beta-number, β (G), of a graph G is defined to be either the smallest positive integer n for which there exists an injective function f : V (G) → {0, 1, . . . , n} such that each uv ∈ E (G) is labeled |f (u) − f (v)| ...