| Autor: |
González-Moreno, Diego, Balbuena, Camino, Olsen, Mika |
| Zdroj: |
Electronic Notes in Discrete Mathematics; Oct2016, Vol. 54, p69-72, 4p |
| Abstrakt: |
Let k ≥ 2 be an integer. Bermond and Thomassen [Bermond J. C., Thomassen, C., Cycles in digraphs a survey, Journal of Graph Theory 5(1) (1981) 1–43] conjectured that every digraph D with δ + ( D ) ≥ 2 k − 1 contains at least k vertex-disjoint cycles. In this work we prove that every bipartite tournament with minimum out-degree at least 2 k − 2 and minimum in-degree at least one contains k vertex-disjoint cycles of length four, whenever k ≥ 3 . Finally, we show that every bipartite tournament with minimum degree at least ( 3 k − 1 ) / 2 contains k vertex-disjoint cycles of length four. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
|
Full Text from ScienceDirect