Incidence dimension and 2-packing number in graphsBožović, Dragana (Avtor) Kelenc, Aleksander (Avtor) Peterin, Iztok (Avtor) Yero, Ismael G. (Avtor) incidence dimensionincidence generator2-packingLet ▫$G=(V,E)$▫ be a graph. A set of vertices ▫$A$▫ is an incidence generator for ▫$G$▫ if for any two distinct edges ▫$e,f \in E(G)$▫ there exists a vertex from ▫$A$▫ which is an endpoint of either ▫$e$▫ or ▫$f$▫. The smallest cardinality of an incidence generator for ▫$G$▫ is called the incidence dimension and is denoted by ▫$\dim_I(G)$▫. A set of vertices ▫$P \subseteq V(G)$▫ is a 2-packing of ▫$G$▫ if the distance in ▫$G$▫ between any pair of distinct vertices from ▫$P$▫ is larger than two. The largest cardinality of a 2-packing of ▫$G$▫ is the packing number of ▫$G$▫ and is denoted by ▫$\rho(G)$▫. In this article, the incidence dimension is introduced and studied. The given results show a close relationship between ▫$\dim_I(G)$▫ and ▫$\rho(G)$▫. We first note that the complement of any 2-packing in graph ▫$G$▫ is an incidence generator for ▫$G$▫, and further show that either ▫$\dim_I(G)=|V(G)|-\rho(G)$▫ or ▫$\dim_I(G)=|V(G)-|\rho(G)-1$▫ for any graph ▫$G$▫. In addition, we present some bounds for ▫$\dim_I(G)$▫ and prove that the problem of determining the incidence dimension of a graph is NP-hard.20222023-08-18 12:55:14Znanstveno delo85102sl