分块矩阵的Drazin 逆不仅在矩阵理论上被广泛研究而且在自动控制、广义系统、概率统计等方面有重要的应用.本文给出了当广义Schur补S = D ? CADB 可逆时，分块矩阵M=[A B C D ]∈ Cmxn ( A,D 是方阵)在满足下列条件之一时的Drazin逆表示：1）BCAπ = O ，BDCAπ = O ，D2CAπ = O ；2）CAπ A2 = O，CAπ BC = O， CAπ BD = O，CAπ AB = O .这些结果推广了文献[9-10,12]的结论.
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