
arXiv: 1609.06961
A graph is said to be well-covered if all its maximal independent sets are of the same size. In 1999, Yamashita and Kameda introduced a subclass of well-covered graphs, called localizable graphs and defined as graphs having a partition of the vertex set into strong cliques, where a clique in a graph is strong if it intersects all maximal independent sets. Yamashita and Kameda observed that all well-covered trees are localizable, pointed out that the converse inclusion fails in general, and asked for a characterization of localizable graphs. In this paper we obtain several structural and algorithmic results about localizable graphs. Our results include a proof of the fact that every very well-covered graph is localizable and characterizations of localizable graphs within the classes of line graphs, triangle-free graphs, $C_4$-free graphs, and cubic graphs, each leading to a polynomial time recognition algorithm. On the negative side, we prove NP-hardness of recognizing localizable graphs within the classes of weakly chordal graphs, complements of line graphs, and graphs of independence number three. Furthermore, using localizable graphs we disprove a conjecture due to Zaare-Nahandi about $k$-partite well-covered graphs having all maximal cliques of size $k$. Our results unify and generalize several results from the literature.
31 pages, 5 figures
Clique cover, FOS: Computer and information sciences, Strong clique, Discrete Mathematics (cs.DM), Characterization, strong clique, Line graph, Graph operations (line graphs, products, etc.), localizable graph, Localizable graph, line graph, Vertex subsets with special properties (dominating sets, independent sets, cliques, etc.), Edge subsets with special properties (factorization, matching, partitioning, covering and packing, etc.), Well-covered graph, info:eu-repo/classification/udc/004, clique cover, FOS: Mathematics, Mathematics - Combinatorics, well-covered graph, characterization, Combinatorics (math.CO), Computer Science - Discrete Mathematics
Clique cover, FOS: Computer and information sciences, Strong clique, Discrete Mathematics (cs.DM), Characterization, strong clique, Line graph, Graph operations (line graphs, products, etc.), localizable graph, Localizable graph, line graph, Vertex subsets with special properties (dominating sets, independent sets, cliques, etc.), Edge subsets with special properties (factorization, matching, partitioning, covering and packing, etc.), Well-covered graph, info:eu-repo/classification/udc/004, clique cover, FOS: Mathematics, Mathematics - Combinatorics, well-covered graph, characterization, Combinatorics (math.CO), Computer Science - Discrete Mathematics
| selected citations These citations are derived from selected sources. This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | 8 | |
| popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network. | Average | |
| influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | Average | |
| impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network. | Top 10% |
