Acknowledgements The author would like to express her deep gratitude to Professor Jun Wang for guiding her into this area and thank the referees for their invaluable suggestions. This work was supported in part by the National Natural Science Foundation of China (Grant Nos. 11001176, 10971138).
Let Ω be a finite set, and let G be a permutation group on Ω. A subset H of G is called intersecting if for any a, 7r H, they agree on at least one point. We show that a maximal intersecting subset of an irreducible...
Supported by National Natural Science Foundation of China (Nos. 10861006, 10401010)
Erdoes and Soes conjectured in 1963 that every graph G on n vertices with edge number e(G) 〉 1/2(k - 1)n contains every tree T with k edges as a subgraph. In this paper, we consider a variation of the above conje...