Matrices whose powers are $M$-matrices or $Z$-matrices

Matrices whose powers approximate the identity

In this paper we characterize the matrices A with the following property: for each ε > 0 there exists k ∈ N such that ‖Ak − I‖ < ε for a given matrix norm. This characterization is applied to the theory of unitary, hermitian nonnegative, positive and stochastic matrices.

Noncirculant Toeplitz Matrices All of Whose Powers Are Toeplitz

Let a, b and c be fixed complex numbers. Let Mn(a, b, c) be the n×n Toeplitz matrix all of whose entries above the diagonal are a, all of whose entries below the diagonal are b, and all of whose entries on the diagonal are c. For 1 6 k 6 n, each k × k principal minor of Mn(a, b, c) has the same value. We find explicit and recursive formulae for the principal minors and the characteristic polyno...

Z{matrices and Inverse Z{matrices

We consider Z{matrices and inverse Z{matrices, i.e. those nonsingular matrices, whose inverse is a Z{matrix. Recently Fiedler and Markham introduced a classii-cation of Z{matrices. This classiication directly leads to a classiication of inverse Z{matrices. Among all classes of Z{matrices and inverse Z{matrices the classes of M{matrices, N 0 {matrices, F 0 {matrices and inverse M{matrices, inver...

E-Clean Matrices and Unit-Regular Matrices

Let $a, b, k,in K$ and $u, v in U(K)$. We show for any idempotent $ein K$, $(a 0|b 0)$ is e-clean iff $(a 0|u(vb + ka) 0)$ is e-clean and if $(a 0|b 0)$ is 0-clean, $(ua 0|u(vb + ka) 0)$ is too.

Two modified Jacobi methods for M-matrices