The class of Z m -well-covered graphs, those in which the cardinality of every maximal independent subset of vertices is congruent to the same number modulo m, contains the well-covered graphs as well as parity graphs. Here we consider such graphs, where there is no small cycle present and obtain a
A Characterization of Well Covered Graphs of Girth 5 or Greater
โ Scribed by A. Finbow; B. Hartnell; R.J. Nowakowski
- Publisher
- Elsevier Science
- Year
- 1993
- Tongue
- English
- Weight
- 998 KB
- Volume
- 57
- Category
- Article
- ISSN
- 0095-8956
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โฆ Synopsis
A graph is well covered if every maximal independent set has the same cardinality. A vertex (x), in a well covered graph (G), is called extendable if (G-{x}) is well covered and (\beta(G)=\beta(G-{x})). If (G) is a connected, well covered graph of girth (\geqslant 5) and (G) contains an extendable vertex then (G) is the disjoint union of edges and 5 -cycles together with a restricted set of edges joining these subgraphs. There are only six connected, well covered graphs of girth (\geqslant 5) which do not contain an extendable vertex. 1993 Academic Press. Inc.
๐ SIMILAR VOLUMES
## Abstract A wellโcovered graph is a graph in which every maximal independent set is a maximum independent set; Plummer introduced the concept in a 1970 paper. The notion of a 1โwellโcovered graph was introduced by Staples in her 1975 dissertation: a wellโcovered graph __G__ is 1โwellโcovered if a
## Abstract A graph is well covered if every maximal independent set has the same cardinality. A vertex __x__, in a wellโcovered graph __G__, is called extendable if __G โ {x}__ is well covered and ฮฒ(__G__) = ฮฒ(__G โ {x}__). If __G__ is a connected, wellโcovered graph containing no 4โ nor 5โcycles
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