Rabern recently proved that any graph with β₯ 3 4 ( +1) contains a stable set meeting all maximum cliques. We strengthen this result, proving that such a stable set exists for any graph with > 2 3 ( +1). This is tight, i.e. the inequality in the statement must be strict. The proof relies on finding a
A Note on Hitting Maximum and Maximal Cliques With a Stable Set
β Scribed by Demetres Christofides; Katherine Edwards; Andrew D. King
- Book ID
- 112121145
- Publisher
- John Wiley and Sons
- Year
- 2012
- Tongue
- English
- Weight
- 506 KB
- Volume
- 73
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
π SIMILAR VOLUMES
For integers m, n β₯ 2, let f (m, n) be the minimum order of a graph where every vertex belongs to both a clique of cardinality m and an independent set of cardinality n. We show that f (m, n) = ( β m -1 + β n -1) 2 .
## Abstract Let __M__ be an arbitrary structure. Then we say that an __M__ βformula __Ο__ (__x__) __defines a stable set in__ __M__ if every formula __Ο__ (__x__) β§ __Ξ±__ (__x__, __y__) is stable. We prove: If __G__ is an __M__ βdefinable group and every definable stable subset of __G__ has __U__ β