Partial Ferrers matrices (Q1343426)

A partial Ferrers matrix is a \((0,1)\)-matrix in which every two columns either both have 1 at the same coordinate or each coordinate of the first is not greater than the corresponding coordinate of the second. For fully indecomposable square partial Ferrers matrices the authors determine the minimum permanent and the minimum number of 1's as a function of the matrix order \(n\).