ELA, Volume 15, pp. 274-284, October 2006, abstract.

Irreducible Toeplitz and Hankel Matrices

Karl-Heinz Forster and Bella Nagy

An infinite matrix is called irreducible if its directed 
graph is strongly connected. It is proved that an infinite 
Toeplitz matrix is irreducible if and only if almost 
every finite leading submatrix is irreducible. An infinite 
Hankel matrix may be irreducible even if all its finite 
leading submatrices are reducible. Irreducibility results 
are also obtained in the finite cases.