Results 1 to 10 of about 8,914 (221)
Spectral norm and energy of a digraph with respect to a VDB topological index [PDF]
HeliyonThe set of singular values of a digraph with respect to a vertex-degree based topological index is the set of all singular values of its general adjacency matrix.
Carlos Espinal, Juan Monsalve, Juan Rada
doaj +2 more sources
Sombor index of directed graphs [PDF]
Heliyon, 2022 Let D be a digraph with set of arcs A. The Sombor index of D is defined asSO(D)=12∑uv∈A(du+)2+(dv−)2,where du+ and dv− are the out-degree and in-degree of the vertices u and v of D.
Roberto Cruz, Juan Monsalve, Juan Rada
doaj +2 more sources
The double competition multigraph of a digraph [PDF]
Discrete Mathematics & Theoretical Computer Science, 2015 In this article, we introduce the notion of the double competition multigraph of a digraph. We give characterizations of the double competition multigraphs of arbitrary digraphs, loopless digraphs, reflexive digraphs, and acyclic digraphs in terms of ...
Yoshio Sano, Jeongmi Park
doaj +1 more source
Dual digraphs of finite semidistributive lattices
Cubo, 2022 Dual digraphs of finite join-semidistributive lattices, meet-semidistributive lattices and semidistributive lattices are characterised. The vertices of the dual digraphs are maximal disjoint filter-ideal pairs of the lattice.
Andrew Craig +2 more
doaj +1 more source
On BMRN*-colouring of planar digraphs [PDF]
Discrete Mathematics & Theoretical Computer Science, 2021 In a recent work, Bensmail, Blanc, Cohen, Havet and Rocha, motivated by applications for TDMA scheduling problems, have introduced the notion of BMRN*-colouring of digraphs, which is a type of arc-colouring with particular colouring constraints.
Julien Bensmail, Foivos Fioravantes
doaj +1 more source
Entropy based Single Valued Neutrosophic Digraph and its applications [PDF]
Neutrosophic Sets and Systems, 2018 This paper introduces the single valued neutrosophic (i.e. SVN) digraph. The basic terminologies and operations of SVN digraphs have been defined. Later certain types of SVN digraphs are shown and some of the important properties of SVN digraphs are ...
Kalyan Sinha, Pinaki Majumdar
doaj +1 more source
Iota energy of weighted digraphs [PDF]
Transactions on Combinatorics, 2018 The eigenvalues of a digraph are the eigenvalues of its adjacency matrix. The iota energy of a digraph is recently defined as the sum of absolute values of imaginary part of its eigenvalues. In this paper, we extend the concept of iota energy of digraphs
Sumaira Hafeez, Mehtab Khan
doaj +1 more source
On Single Valued Neutrosophic Signed Digraph and its applications [PDF]
Neutrosophic Sets and Systems, 2018 The development of the theory of the single valued neutrosophic (SVN) digraph is done in this paper. Also this paper introduces the concept of SVN signed digraph.
K. Sinha, P. Majumdar
doaj +1 more source
A note on the Roman domatic number of a digraph [PDF]
Communications in Combinatorics and Optimization, 2020 A {\em Roman dominating function} on a digraph $D$ with vertex set $V(D)$ is a labeling $f\colon V(D)\to \{0, 1, 2\}$ such that every vertex with label $0$ has an in-neighbor with label $2$. A set $\{f_1,f_2,\ldots,f_d\}$ of Roman dominating functions
Lutz Volkmann, D. Meierling
doaj +1 more source
Resolvable Networks—A Graphical Tool for Representing and Solving SAT
Mathematics, 2021 In this paper, we introduce the notion of resolvable networks. A resolvable network is a digraph of subnetworks, where subnetworks may overlap, and the inner structure of subnetworks are not interesting from the viewpoint of the network.
Gábor Kusper, Csaba Biró, Benedek Nagy
doaj +1 more source