In the author's Ph. D thesis, a non-quasiprimitive graph admitting a quasiprimitive automorphism group isomorphic to J1 was constructed ,where J1 is Janko simple group of order 175560. Is this the only one for J1? I...In the author's Ph. D thesis, a non-quasiprimitive graph admitting a quasiprimitive automorphism group isomorphic to J1 was constructed ,where J1 is Janko simple group of order 175560. Is this the only one for J1? In this paper all primitive (J1,2)-arc transitive graphs Г are given and that AutГ≌J1 is proved.展开更多
For a prime p at least 5,let T=PSL(2,p).This paper gives a classification of the connected arc-transitive cubic Cayley graphs on T and a determination of the gener- ated pairs ((?),(?)) of T such that o((?))=2 and o((...For a prime p at least 5,let T=PSL(2,p).This paper gives a classification of the connected arc-transitive cubic Cayley graphs on T and a determination of the gener- ated pairs ((?),(?)) of T such that o((?))=2 and o((?))=3.展开更多
Let Г be a simple connected graph and let G be a group of automorphisms of Г. Г is said to be (G, 2)-arc transitive if G is transitive on the 2-arcs of Г. It has been shown that there exists a family of non-quas...Let Г be a simple connected graph and let G be a group of automorphisms of Г. Г is said to be (G, 2)-arc transitive if G is transitive on the 2-arcs of Г. It has been shown that there exists a family of non-quasiprimitive (PSU3(q), 2)-arc transitive graphs where q = 2^3m with m an odd integer. In this paper we investigate the case where q is an odd prime power.展开更多
In this paper, we discuss the G-decomposition of λKv into 6-circuits with two chords. We construct some holey G-designs using sharply 2-transitive group, and present the recursive structure by PBD. We also give a uni...In this paper, we discuss the G-decomposition of λKv into 6-circuits with two chords. We construct some holey G-designs using sharply 2-transitive group, and present the recursive structure by PBD. We also give a unified method to construct G-designs when the index equals the edge number of the discussed graph. Finally, the existence of G-GDλ(v) is given.展开更多
基金Supported by the National Natural Science Foundation of China(10471152).
文摘In the author's Ph. D thesis, a non-quasiprimitive graph admitting a quasiprimitive automorphism group isomorphic to J1 was constructed ,where J1 is Janko simple group of order 175560. Is this the only one for J1? In this paper all primitive (J1,2)-arc transitive graphs Г are given and that AutГ≌J1 is proved.
基金supported by National Natural Science Foundation of the People’s Republic of China“On the symmetries and local properties of graphs with square-free order”(11601005)Anhui Provincial Science Fund for Excellent Young Scholars“On the symmetries of edge-primitive graphs with square-free order”(gxyq2020011).
基金supported by the National natural Science Foundation of China(Grant No.10371003)Beijing Natural Science Foundation(Grant no.1052005)BMCE(Grant No.KM 2004 10028001).
文摘For a prime p at least 5,let T=PSL(2,p).This paper gives a classification of the connected arc-transitive cubic Cayley graphs on T and a determination of the gener- ated pairs ((?),(?)) of T such that o((?))=2 and o((?))=3.
基金the National Natural Science Foundation of China (10471152)
文摘Let Г be a simple connected graph and let G be a group of automorphisms of Г. Г is said to be (G, 2)-arc transitive if G is transitive on the 2-arcs of Г. It has been shown that there exists a family of non-quasiprimitive (PSU3(q), 2)-arc transitive graphs where q = 2^3m with m an odd integer. In this paper we investigate the case where q is an odd prime power.
基金Foundation item: the National Natural Science Foundation of China (No. 10671055) the Natural Science Foundation of Hebei Province (No. A2007000230) the Foundation of Hebei Normal University (No. L2007B22).
文摘In this paper, we discuss the G-decomposition of λKv into 6-circuits with two chords. We construct some holey G-designs using sharply 2-transitive group, and present the recursive structure by PBD. We also give a unified method to construct G-designs when the index equals the edge number of the discussed graph. Finally, the existence of G-GDλ(v) is given.