Supported by the National Natural Science Foundation of China(Grant No.11801092);the Characteristic Innovation Project(Natural Science)of Guangdong Province(Grant No.2018KTSCX160);the Fund of Guangzhou Science and Technology(Grant No.201804010088)。
In recent years several authors have determined some 2-designs with flag-transitive point-primitive automorphism group G of almost simple type with sporadic socle. Here we obtain the complete classification of flag-tr...
Supported by the National Natural Science Foundation of China(Grant Nos.11471123;11626206);the Scientific Research Foundation for Excellent Talents of Xuzhou Medical University(Grant No.D2016002)
Let D be a nontrivial symmetric(v, k, 4) design, and G ≤ Aut(D) be flag-transitive and point-primitive with PSL_n(q) as socle. Then D is a 2-(15, 8, 4) symmetric design and Soc(G) = PSL_2(9).
Supported by the National Natural Science Foundation of China(Grant Nos.11471123;11426066);the Natural Science Foundation of Guangdong Province(Grant No.S2013010011928)
Let D be a nontrivial symmetric(v, k, λ) design, and G be a subgroup of the full automorphism group of D. In this paper we prove that if G acts flag-transitively, pointprimitively on D and Soc(G) = PSL(2, q), t...
Supported by the National Natural Science Foundation of China(Grant Nos.10901061;11071088);the Zhujiang Technology New Star Foundation of Guangzhou(Grant No.2011J2200090);Program on International Cooperation and Innovation of Guangdong Province Education Department(Grant No.2012gjhz0007)
Recently, the primitive symmetric signed digraphs on $n$ vertices with the maximum base 2n and the primitive symmetric loop-free signed digraphs on n vertices with the maximum base 2n-1 are characterized, respectively...
Supported by the National Natural Science Foundation of China(Grant Nos.10901061;11071088);Programon International Cooperation and Innovation,Department of Education,Guangdong Province(Grant No.2012gjhz0007);the Zhujiang Technology New Star Foundation of Guangzhou City(Grant No.2011J2200090)
Let S be a primitive non-powerful symmetric loop-free signed digraph on even n vertices with base 3 and minimum number of arcs. In [Lihua YOU, Yuhan WU. Primitive non- powerful symmetric loop-free signed digraphs with...
Supported by the National Natural Science Foundation of China(Grant Nos.10901061;11071088);the Zhujiang Technology New Star Foundation of Guangzhou(Grant No.2011J2200090)
In this paper, we study the bases and base sets of primitive symmetric loop-free (generalized) signed digraphs on n vertices. We obtain sharp upper bounds of the bases, and show that the base sets of the classes of ...