Changing and unchanging of the domination number of a graph: path addition numbers
نویسندگان
چکیده
Given a graph $G = (V,E)$ and two its distinct vertices $u$ $v$. The $(u,v)$-$P_k$-{\em addition graph} of $G$ is the $G_{u,v,k-2}$ obtained from disjoint union path $P_k: x_0,x_1,..,x_{k-1}$, $k \geq 2$, by identifying $x_0$, $v$ $x_{k-1}$. We prove that (a) $ \gamma(G)-1 \leq \gamma(G_{u,v,k})$ for all 1$, (b) $\gamma(G_{u,v,k}) > \gamma(G)$ when 5$. also provide necessary sufficient conditions equality to be valid each pair $u,v \in V(G)$.
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ژورنال
عنوان ژورنال: Discussiones Mathematicae Graph Theory
سال: 2021
ISSN: ['1234-3099', '2083-5892']
DOI: https://doi.org/10.7151/dmgt.2189