Böttcher, A.A.BöttcherEmbree, M.M.EmbreeLindner, MarkoMarkoLindner2021-10-252021-10-252002-12-03Integral Equations and Operator Theory 42 (2): 142-165 (2002-12-03)http://hdl.handle.net/11420/10577This paper explores the relationship between the spectra of perturbed infinite banded Laurent matrices L(a) + K and their approximations by perturbed circulant matrices Cn(a) + PnKPn for large n. The entries Kjk of the perturbation matrices assume values in prescribed sets Ωjk at the sites (j, k) of a fixed finite set E, and are zero at the sites (j, k) outside E. With KΩE denoting the ensemble of these perturbation matrices, it is shown that limn→∞ ∪K∈κΩE sp(Cn(a) + PnKPn) = ∪K∈κΩE sp(L(a) + K) under several fairly general assumptions on E and Ω.en1420-898920022142165MathematikJournal Article10.1007/BF01275512Other