- Tytuł:
- Some Toughness Results in Independent Domination Critical Graphs
- Autorzy:
-
Ananchuen, Nawarat
Ananchuen, Watcharaphong - Powiązania:
- https://bibliotekanauki.pl/articles/31339252.pdf
- Data publikacji:
- 2015-11-01
- Wydawca:
- Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
- Tematy:
-
domination critical
toughness - Opis:
- A subset $ S $ of $ V (G) $ is an independent dominating set of $ G $ if $ S $ is independent and each vertex of $ G $ is either in $ S $ or adjacent to some vertex of $ S $. Let $ i(G) $ denote the minimum cardinality of an independent dominating set of $ G $. A graph $ G $ is $k$-$i$-critical if $ i(G) = k $, but $ i(G+uv) < k $ for any pair of non-adjacent vertices $ u $ and $ v $ of $ G $. In this paper, we establish that if $ G $ is a connected 3-$i$-critical graph and $S$ is a vertex cutset of $G$ with $ |S| ≥ 3 $, then $ \omega ( G - S ) \leq \frac{1+\sqrt{8|S|+1}}{2} $, improving a result proved by Ao [3], where $\omega(G−S)$ denotes the number of components of $G−S$. We also provide a characterization of the connected 3-$i$-critical graphs $G$ attaining the maximum number of $ \omega(G − S)$ when $S$ is a minimum cutset of size 2 or 3.
- Źródło:
-
Discussiones Mathematicae Graph Theory; 2015, 35, 4; 703-713
2083-5892 - Pojawia się w:
- Discussiones Mathematicae Graph Theory
- Dostawca treści:
- Biblioteka Nauki