Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6423646 | Electronic Notes in Discrete Mathematics | 2016 | 4 Pages |
Abstract
Let kâ¥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)â¥2kâ1 contains at least k vertex-disjoint cycles. In this work we prove that every bipartite tournament with minimum out-degree at least 2kâ2 and minimum in-degree at least one contains k vertex-disjoint cycles of length four, whenever kâ¥3. Finally, we show that every bipartite tournament with minimum degree at least (3kâ1)/2 contains k vertex-disjoint cycles of length four.
Related Topics
Physical Sciences and Engineering
Mathematics
Discrete Mathematics and Combinatorics
Authors
Diego González-Moreno, Camino Balbuena, Mika Olsen,