Bulletin of the
Korean Mathematical Society BKMS

Let $G=(V,E)$ be a graph. A function $f:V\rightarrow\{-1,+1\}$ defined on the vertices of $G$ is a signed total dominating function if the sum of its function values over any open neighborhood is at least one. The signed total domination number of $G$, $\gamma_t^s(G)$, is the minimum weight of a signed total dominating function of $G$. In this paper, we study the signed total domination number of generalized Petersen graphs $P(n,2)$ and prove that for any integer $n\geq 6$, $\gamma_t^s(P(n,2))= 2\lfloor \frac{n}{3} \rfloor + 2t$, where $t \equiv n (\mbox{mod }3)$ and $0\le t\le 2$.

Keywords: signed total domination, generalized Petersen graph

MSC numbers: 05C50, 05C69