## Abstract Our main result is the following theorem. Let __k__ββ₯β2 be an integer, __G__ be a graph of sufficiently large order __n__, and __Ξ΄__(__G__)ββ₯β__n__/__k__. Then: __G__ contains a cycle of length __t__ for every even integer __t__βββ[4, __Ξ΄__(__G__)β+β1]. If __G__ is nonbipartite then
On cycle lengths in graphs of moderate degree
β Scribed by H. Bencherif Ait-Djafer
- Publisher
- Elsevier Science
- Year
- 1994
- Tongue
- English
- Weight
- 447 KB
- Volume
- 125
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
β¦ Synopsis
We show that for all positive E, an integer N(E) exists such that if G is any graph of order n>N(s) with minimum degree 63324 then G contains a cycle of length 21 for each integer 1, 2<1<~/(16+s). Bondy [4] and Woodall [15] have obtained sufficient conditions for a graph to contain cycles of each length 2, 3 < I < m, where m is a constant. Subsequently, several authors [3, 5, 12-141 proved results which support Bondy's metaconjecture.
We state sufficient conditions in terms of minimum degree for a graph to contain cycles of specified lengths.
We start with a result due to Dirac.
Theorem 1.1 (Dirac [9]). Let G be a graph of order n > 3, with minimum degree 6 2 n/2.
Then G is Hamiltonian.
The following result of Bondy generalizes Theorem 1.1.
Theorem 1.2 (Bondy [ 51). Let G be a graph of order n> 3, with minimum degree 6 >n/2. Then G is pancyclic unless n is even and G is the complete bipartite graph K./z, n/2.
π SIMILAR VOLUMES
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The set of different cycle lengths of a graph G is denoted by C(G). We study how the distribution of C(G) depends on the minimum degree of G. We prove two results indicating that C(G) is dense in some sense. These results lead to the solution of a conjecture of Erdos and Hajnal stating that for suit
## Abstract An old conjecture of ErdΕs states that there exists an absolute constant __c__ and a set __S__ of density zero such that every graph of average degree at least __c__ contains a cycle of length in __S__. In this paper, we prove this conjecture by showing that every graph of average degre
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