Offensive k-alliances in graphs

H. Fernau, J. A. Rodriguez, J. M. Sigarreta

Let $G=(V,E)$ be a simple graph. For a nonempty set $X\subset V,$ and a vertex $v\in V,$ ${\delta }_X(v)$ denotes the number of neighbors $v$ has in $X.$ A nonempty set $S\subset V$ is a…