## Abstract By a result of Gallai, every finite graph __G__ has a vertex partition into two parts each inducing an element of its cycle space. This fails for infinite graphs if, as usual, the cycle space is defined as the span of the edge sets of finite cycles in __G__. However, we show that, for t
Cycle and cocycle coverings of graphs
β Scribed by Sean McGuinness
- Publisher
- John Wiley and Sons
- Year
- 2010
- Tongue
- English
- Weight
- 161 KB
- Volume
- 65
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
β¦ Synopsis
In this article, we show that for any simple, bridgeless graph G on n vertices, there is a family C of at most n-1 cycles which cover the edges of G at least twice. A similar, dual result is also proven for cocycles namely: for any loopless graph G on n vertices and edges having cogirth g * β₯ 3 and k(G) components, there is a family of at most -n+k(G) cocycles which cover the edges of G at least twice.
π SIMILAR VOLUMES
Some new results on minimum cycle covers are proved. As a consequence, it is obtained that the edges of a bridgeless graph G can be covered by cycles of total length at most |E(G)| + 25 24 (|V (G)| -1), and at most |E(G)| + |V (G)| -1 if G contains no circuit of length 8 or 12.
In this article, we study cycle coverings and 2-factors of a claw-free graph and those of its closure, which has been defined by the first author (On a closure concept in claw-free graphs, J Combin Theory Ser B 70 (1997), 217-224). For a claw-free graph G and its closure cl(G), we prove: ( 1 (2) G
## Abstract Let __G__ be a graph of order __n__ β₯ 5__k__ + 2, where __k__ is a positive integer. Suppose that the minimum degree of __G__ is at least β(__n__ + __k__)/2β. We show that __G__ contains __k__ pentagons and a path such that they are vertexβdisjoint and cover all the vertices of __G__. M
## Abstract Let __G__ be a bridgeless cubic graph. We prove that the edges of __G__ can be covered by circuits whose total length is at most (44/27) |__E(G)__|, and if Tutte's 3βflow Conjecture is true, at most (92/57) |__E(G)__|.
## Abstract Let __k__ and __n__ be two integers such that __k__ β₯ 0 and __n__ β₯ 3(__k__ + 1). Let __G__ be a graph of order __n__ with minimum degree at least β(__n__ + __k__)/2β. Then __G__ contains __k__ + 1 independent cycles covering all the vertices of __G__ such that __k__ of them are triangl