Let T2k+1 be the set of trees on 2k+1 vertices with nearly perfect matchings and α(T) be the algebraic connectivity of a tree T. The authors determine the largest twelve values of the algebraic connectivity of th...Let T2k+1 be the set of trees on 2k+1 vertices with nearly perfect matchings and α(T) be the algebraic connectivity of a tree T. The authors determine the largest twelve values of the algebraic connectivity of the trees in T2k+1. Specifically, 10 trees T2,T3,... ,T11 and two classes of trees T(1) and T(12) in T2k+1 are introduced. It is shown in this paper that for each tree T^′1,T^″1∈T(1)and T^′12,T^″12∈T(12) and each i,j with 2≤i〈j≤11,α(T^′1)=α(T^″1)〉α(Tj)〉α(T^′12)=α(T^″12).It is also shown that for each tree T with T∈T2k+1/(T(1)∪{T2,T3,…,T11}∪T(12)),α(T^′12)〉α(T).展开更多
文摘Let T2k+1 be the set of trees on 2k+1 vertices with nearly perfect matchings and α(T) be the algebraic connectivity of a tree T. The authors determine the largest twelve values of the algebraic connectivity of the trees in T2k+1. Specifically, 10 trees T2,T3,... ,T11 and two classes of trees T(1) and T(12) in T2k+1 are introduced. It is shown in this paper that for each tree T^′1,T^″1∈T(1)and T^′12,T^″12∈T(12) and each i,j with 2≤i〈j≤11,α(T^′1)=α(T^″1)〉α(Tj)〉α(T^′12)=α(T^″12).It is also shown that for each tree T with T∈T2k+1/(T(1)∪{T2,T3,…,T11}∪T(12)),α(T^′12)〉α(T).