文章对含有三个圈的本原不可幂定号有向图S进行研究,S的基础图是本原有向图,用D表示.利用反证法,我们得到了D的第一类广义本原指数并在此基础上得到了S的local基.
A primitive non-powerful signed digraph S that contains three circles was stud-ied. The under graph of S is a primitive digraph,denoted by D. Using the reduction to absurdity,we obtain the local exponents of D, and on this basis we get the local bases of S.