Disjoint cycles in star-free graphs
โ Scribed by Markus, Lisa R.; Snevily, Hunter S.
- Publisher
- John Wiley and Sons
- Year
- 1996
- Tongue
- English
- Weight
- 322 KB
- Volume
- 21
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
โฆ Synopsis
A graph is claw-free if it does not contain K l , 3 as an induced subgraph. It is Kl,,-free if it does not contain K l , r as an induced subgraph. We show that if a graph is Kl,,-free ( r 2 4), only p + 2r -1 edges are needed to insure that G has t w o disjoint cycles.
As an easy consequence w e get a well-known result of Posa's. 0 1996 John Wiley & Sons. Inc.
Let G be a K,,,-free graph (Y 2 4). If q 2 p + 2r -1 then G contains As a corollary we get the following well-known result of Posa.
๐ SIMILAR VOLUMES
We prove that any k-regular directed graph with no parallel edges contains a collection of at least fl(k2) edge-disjoint cycles; we conjecture that in fact any such graph contains a collection of at least ( lCi1 ) disjoint cycles, and note that this holds for k 5 3. o 1996
Three problems in connection with cycles on the butterfly graphs are studied in this paper. The first problem is to construct complete uniform cycle partitions for the butterfly graphs. Suppose that
Let G n,m,k denote the space of simple graphs with n vertices, m edges, and minimum degree at least k, each graph G being equiprobable. Let G have property A k , if G contains (k -1)/2 edge disjoint Hamilton cycles, and, if k is even, a further edge disjoint matching of size n/2 . We prove that, for
In this article, we establish bounds for the length of a longest cycle C in a 2-connected graph G in terms of the minimum degree ฮด and the toughness t. It is shown that C is a Hamiltonian cycle or |C| โฅ (t + 1)ฮด + t.