## Abstract A __kβtree__ is a chordal graph with no (__k__β+β2)βclique. An ββ__treeβpartition__ of a graph __G__ is a vertex partition of __G__ into βbags,β such that contracting each bag to a single vertex gives an ββtree (after deleting loops and replacing parallel edges by a single edge). We pro
A generalization of chordal graphs
β Scribed by P. D. Seymour; R. W. Weaver
- Publisher
- John Wiley and Sons
- Year
- 1984
- Tongue
- English
- Weight
- 487 KB
- Volume
- 8
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
β¦ Synopsis
In a 3-connected planar triangulation, every circuit of length 2 4 divides the rest of the edges into two nontrivial parts (inside and outside) which are "separated" by the circuit. Neil Robertson asked to what extent triangulations are characterized by this property, and conjectured an answer. In this paper we prove his conjecture, that if G is simple and 3-connected and every circuit of length 3 4 has at least two "bridges," then G may be built up by "clique-sums" starting from complete graphs and planar triangulations. This is a generalization of Dirac's theorem about chordal graphs.
π SIMILAR VOLUMES
We prove that every planar graph on \(n\) vertices is contained in a chordal graph with at most \(c n \log n\) edges for some abolsute constant \(c\) and this is best possible to within a constant factor. 1994 Academic Press, Inc.
## Abstract The clique graph __K__(__G__) of a graph is the intersection graph of maximal cliques of __G.__ The iterated clique graph __K__^__n__^(__G__) is inductively defined as __K__(K^nβ1^(__G__)) and __K__^1^(__G__) = __K__(__G__). Let the diameter diam(__G__) be the greatest distance between
The interval number of a (simple, undirected) graph G is the least positive integer t such that G is the intersection graph of sets, each of which is the union of t real intervals. A chordal (or triangulated) graph is one with no induced cycles on 4 or more vertices. If G is chordal and has maximum
## Abstract Suppose __G = (V, E)__ is a graph in which every vertex __x__ has a nonβnegative real number __w(x)__ as its weight. The __w__βdistance sum of a vertex __y__ is __D~G, w~(y)__ = Ο~xβ v~ __d(y, x)w(x).__ The __w__βmedian of __G__ is the set of all vertices __y__ with minimum __w__βdistanc