由树构造的A(H)=3图

Graphs with A(H)=3 Constructed from Trees

树T的A(T)值的确定已得到完整的刻画,根据树的A(T)值特点,考虑树的A(T)值与一般有限无向图H的A(H)值之间关系,由树出发,构造出A(H)=3图.给出按树的中心的不同构造A(H)=3图的两种相应方法:中心加点法和中心加边法.证明了可以由树构造出任意n(n≥6)阶的A(H)=3图.

How to determine the parameter A（T） of a tree have been known. According to the characteristic of parameter A （ T）, to consider what relation exists between A （H） and A （ T）, and construct a graph with A （H） = 3 from a tree. Two ways of constructing graphs with A（H） =3 are given. They are center pulsing vertex and center pulsing edges, and It is confirmed probably to construct willful order n（n≥6） graphs with A（H） =3.