The characterization and construction of minimal forbidden configuration ( MFC) of strong sign nonsingular digraph ( simplifed as S 2NS digraph) are concerned by many researchers. 强符号非异有向图(简称S2NS有向图)的极小禁用子图(简称MFC)的判定和构造等问题是众多学者所关心的问题。
Let D be a strong digraph of order 2r+ 3 and the minimum indegree and outdegree at least r(≥ 2). 设D是阶为2r+3的强连通有向图,最小内次和外次至少r(≥2)。
The asso-ciated digraph of a primitive nearly reducible matrix is a primitive minimally strong digraph. 研究本原几乎可约矩阵的k-指数等价于研究本原极小强连通有向图的k-指数。