Let G be a graph with integral edge weights. A function d : V (G) → Zp is called a nowhere 0 mod p domination function if each v ∈ V satisfies ( d(v) + ∑ u∈N(v) w(u, v)d(u) ) 6= 0 mod p, where w(u, v) denotes the weight of the edge (u, v) and N(v) is the neighborhood of v. The subset of vertices with d(v) 6= 0 is called a nowhere 0 mod p dominating set. It is known that every graph has a nowher...

let $k$ be a positive integer. a subset $s$ of $v(g)$ in a graph $g$ is a $k$-tuple total dominating set of $g$ if every vertex of $g$ has at least $k$ neighbors in $s$. the $k$-tuple total domination number $gamma _{times k,t}(g)$ of $g$ is the minimum cardinality of a $k$-tuple total dominating set of $g$. if$v(g)=v^{0}={v_{1}^{0},v_{2}^{0},ldots ,v_{n}^{0}}$ and $e(g)=e_{0}$, then for any in...

Domination in graphs has been an extensively researched branch of graph theory. Graph theory is one of the most flourishing branches of modern mathematics and computer applications. An introduction and an extensive overview on domination in graphs and related topics is surveyed and detailed in the two books by Haynes et al. [ 1, 2]. Recently dominating functions in domination theory have receiv...

Preprocessing by data reduction is a simple but powerful technique used for practically solving different network problems. A number of empirical studies shows that a set of reduction rules for solving Dominating Set problems introduced by Alber, Fellows & Niedermeier leads efficiently to optimal solutions for many realistic networks. Despite of the encouraging experiments, the only class of gr...

Classical voting rules output a winning alternative (or a nonempty set of tied alternatives). Social welfare functions output a ranking over alternatives. There are many practical situations where we have to output a different structure than a winner or a ranking: for instance, a ranked or non-ranked set of k winning alternatives, or an ordered partition of alternatives. We define three classes...

A graph is bicritical if the removal of any pair of vertices decreases the domination number. We study properties of bicritical graphs and their relation with critical graphs. Next we obtain results for bicritical graphs with edge connectivity two or three. We also generalize the notion of the coalescence of two graphs, and we investigate the bicriticality of such graphs.

In a graph, an edge is said to dominate itself and its adjacent edges. Given an undirected and edge-weighted graph G = (V,E) and an integer k, Max Edge Domination problem (MaxED) is to find a subset K ⊆ E with cardinality at most k such that total weight of edges dominated by K is maximized. MaxED is NP-hard due to the NP-hardness of the minimum edge dominating set problem. In this paper, we pr...

We continue the study of restrained double Roman domination in graphs. For a graph $G=\big{(}V(G),E(G)\big{)}$, dominating function $f$ is called (RDRD function) if subgraph induced by $\{v\in V(G)\mid f(v)=0\}$ has no isolated vertices. The number number) $\gamma_{rdR}(G)$ minimum weight $\sum_{v\in V(G)}f(v)$ taken over all RDRD functions $G$. first prove that problem computing $\gamma_{rdR}$...