报告人：季利均（苏州大学）

时间：2021年4月16日10:30开始

腾讯会议ID:539 242 689（无密码）

摘要:Let G be an abelian group of order v.  A Steiner quadruple system of order v (SQS(v)) (G, B) is called symmetric K-invariant if for each B∈B, it holds that B+g∈B for each g∈G and B=-B+g’ for some g’∈G. When the Sylow 2-subgroup of G is cyclic, Munemasa and Sawa gave a necessary and sufficient condition for the existence of a symmetric G-invariant SQS(v) (2012), which is a generalization of a necessary and sufficient condition for the existence of a symmetric cyclic SQS(v) by Piotrowski (1985). In this talk, we give that a symmetric G-invariant SQS(v) exists if and only if v≡ 2,4 mod 6, the order of each element of G is not divisible by 8 and there exists a symmetric cyclic SQS(2p) for any odd prime divisor p of v.

简介:季利均，苏州大学数学科学学院教授，主要研究方向为组合设计与组合编码。作为主要成员参与完成两项国家自然科学基金重点项目，主持完成一项国家自然科学基金优秀青年项目，获国际组合数学及其应用协会（ICA，Institute of Combinatorics and its Applications）2015年度霍尔(Hall)奖。

邀请人：傅士硕

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