Eigenvalues of matrices with several prescribed blocks Original Research Article

A previous paper by D. Hershkowitz [Linear and Multilinear Algebra 14 (1983) 315–342] described the possible eigenvalues of an n×n matrix when 2n−3 entries are fixed and the others vary. This paper describes the possible eigenvalues of a pk×pk matrix, partitioned into k×k blocks of size p×p when 2k−3 blocks are fixed and the others vary.