Let G(V,E) be a finite, undirected, simple graph without isolated vertices. A dominating set D of V(G) is called degree coprime G if for every v∈V-D, there exist vertex u∈D such that uv∈E(G) and (deg u,deg v)=1. The minimum cardinality the domination number denoted by γ_cp (G). non-coprime v)≠1. γ_ncp We obtain some graphs.

a disk wang-bézier type generalized ball curve is a wang-bézier type generalized ball curve whose control points are disks in a plane. it can be viewed as a parametric curve with error tolerances. in this paper, we discuss the problem of degree reduction of disk wang-bézier type generalized ball curve, that is, bounding disk wang-bézier type generalized ball curves with lower degree disk wang-b...

the probability that the commutator of two group elements is equal to a given element has been introduced in literature few years ago. several authors have investigated this notion with methods of the representation theory and with combinatorial techniques. here we illustrate that a wider context may be considered and show some structural restrictions on the group.