小直径双圈图的永久和  

Onthe Permanental Sums of Bicyclic Graphswith Small Diameter

作　　者：蔚勇 吴廷增[1] YU Yong;WU TingGzeng(School of Mathematics and Statistics,Qinghai Minzu University,Xining810007,China)

机构地区：[1]青海民族大学数学与统计学院,西宁810007

出　　处：《青岛大学学报（自然科学版）》2023年第1期1-7,14,共8页Journal of Qingdao University(Natural Science Edition)

基　　金：国家自然科学基金(批准号:12261071)资助;青海省自然科学基金(批准号:2020-ZJ-920)资助。

摘　　要：研究了小直径双圈图永久和的性质,确定了直径为2的双圈图永久和的界。特别地,确定了直径为3的双圈图的永久和上界,并刻画了其极图。The properties of permanental sums of bicyclic graphs with small diameter were studied,and the bound of permanental sums of bicyclic graphs with diameter two were determined.In particular,the sharp upper bound of the permanental sums of bicyclic graphs with diameter three were determined,and the corresponding extremal bicyclic graphs were also characterized.

关 键 词：积和式 积和多项式 永久和 直径 双圈图 

分 类 号：O157.5[理学—数学]