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arXiv · 2202.09594

Independent domination of graphs with bounded maximum degree

Eun-Kyung Cho·Jinha Kim·Minki Kim·Sang-il Oum
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Abstract

An independent dominating set of a graph, also known as a maximal independent set, is a set $S$ of pairwise non-adjacent vertices such that every vertex not in $S$ is adjacent to some vertex in $S$. We prove that for $\Delta=4$ or $\Delta\ge 6$, every connected $n$-vertex graph of maximum degree at most $\Delta$ has an independent dominating set of size at most $(1-\frac{\Delta}{\lfloor\Delta^2/4\rfloor+\Delta})(n-1)+1$. In addition, we characterize all connected graphs having the equality and we show that other connected graphs have an independent dominating set of size at most $(1-\frac{\Delta}{ \lfloor\Delta^2/4\rfloor+\Delta})n$.

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Eun-Kyung Cho, Jinha Kim, Minki Kim, Sang-il Oum. 2022-02-19. Independent domination of graphs with bounded maximum degree. https://doi.org/10.1016/j.jctb.2022.10.004

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