r-Indecomposable and r-Nearly Decomposable Matrices
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چکیده
Let n, r be integers with 0 ≤ r ≤ n− 1. An n×n matrix A is called r-partly decomposable if it contains a k×l zero submatrix with k+l = n−r+1. A matrix which is not r-partly decomposable is called r-indecomposable (shortly, r-inde). Let Eij be the n × n matrix with a 1 in the (i, j) position and 0’s elsewhere. If A is r-indecomposable and, for each aij 6= 0, the matrix ∗Research supported by National Natural Science Foundation of China (No.10331020) and NNSF of Guangdong Province (No.04010389).
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تاریخ انتشار 2005